JPH04291249A - Photographic film and information recording method - Google Patents

Abstract

PURPOSE:To obtain a photographic film capable of easily detecting a film carrying velocity and an information recording method capable of surely recording the information on the magnetic recording part of the photographic film. CONSTITUTION:A magnetic recording layer coated with a transparent magnetic body is arranged on the back surface of the photographic film, and the magnetic recording layer is constituted of a large number of tracks (a track S1 is illustrated by a selected Figure). Clock areas 18 and 20 for recording a clock signal in advance is arranged on the leading end and the trailing end of each track. At the time of recording the information, the photographic film carrying velocity is judged based on the frequency of the clock signal which is detected by a magnetic head, and the information is recorded after the frequency of the clock signal becomes equal to or exceeding a prescribed value.

Description

[Detailed description of the invention]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photographic film having a magnetic recording section and an information recording method using this photographic film.

2. Description of the Related Art A transparent magnetic material is applied to a photographic film, particularly a negative film, to form a magnetic recording area along the conveyance direction of the negative film, and information about the negative film and information about the images printed on the negative film is stored in the magnetic recording area. It has been proposed to record on a magnetic recording section (for example, I
International Publication
Number WO 90/04205). According to this, information related to an image can be recorded in the magnetic recording section of a part that physically corresponds to the image frame in which the image is recorded, which saves the trouble of searching, etc. You can input the date and time, shooting location, shooting conditions, etc. Further, in a laboratory, when printing onto photographic paper, it is possible to record the exposure amount, etc. at the time of printing for each image frame. Therefore, when reordering, by reading the recorded exposure amount, etc., the printing process can be performed under the same conditions. By the way, information is recorded on the magnetic recording section by operating a magnetic head or the like while the negative film is being conveyed.
If the conveyance speed of the negative film is below a predetermined value, even if information is recorded in the magnetic recording section, it will not be possible to reproduce it with the magnetic head. On the other hand, in a transport system that transports negative film using a drive means such as a motor, if the film is transported with a constant driving force from the start of transport, a large torque may be applied to the negative film, especially immediately after the start of transport, which may adversely affect the negative film. be. For this reason, in the conveyance system, the motor etc. are controlled so that the conveyance speed of the negative film gradually increases as shown in FIG. 12 after the start of conveyance. Therefore, during the T seconds from when the negative film starts being conveyed until the conveying speed of the negative film reaches a speed V (for example, 30 mm/sec) at which information can be recorded in the magnetic recording section, information is not stored in the magnetic recording section. cannot be recorded. For this reason, a non-recording section is provided for a certain length from the start of transport, where magnetic recording is not performed, and this non-recording section is detected by perforations provided in the negative film, and the transport speed is adjusted after passing through the non-recording section. Recording is started after the speed increases to V.

[Problems to be Solved by the Invention] However, the accuracy of detection using the perforations is low, and it is not possible to reliably detect non-detection sections when the perforations are cut or the like. In addition, for example, if a camera records the date and time of photography, location, photography conditions, etc. during photography, even after passing through a non-recording section due to a drop in the voltage of the battery that powers the transport system, etc. There were cases where the conveyance speed did not exceed a predetermined value and information could not be recorded. To prevent this, it is possible to detect the voltage of the battery or the rotational speed of the motor's drive shaft, and if the detected value falls below a certain value, an alarm is issued to prompt the user to replace the battery, etc. Although this is possible, since it is necessary to newly provide a detection means, the configuration becomes complicated and the cost increases. Also,
Multiple tracks are provided in the magnetic recording section along the negative film transport direction, information is recorded on one track and only a clock signal is recorded on the other track, and the film transport speed is determined by reading this clock signal. However, it is necessary to provide a magnetic head dedicated to reading the clock signal corresponding to the track where only the clock signal is recorded, which complicates the configuration and increases cost. The present invention was made in consideration of the above-mentioned facts, and an object of the present invention is to obtain a photographic film whose film transport speed can be easily detected. Another object of the present invention is to obtain an information recording method that can reliably record information on the magnetic recording section of a photographic film.

[Means for solving the problem] The invention according to claim 1 includes:
A photographic film that is provided with a magnetic recording section and in which information is recorded along a predetermined direction in a recording area of the magnetic recording section,
A clock area in which a clock signal is recorded is provided at least in a magnetic recording section upstream of the recording area in the predetermined direction. The invention according to claim 2 provides a method for recording information along a predetermined direction in a recording area of a magnetic recording part provided on a photographic film, by applying a clock signal to at least a magnetic recording part on the upstream side of the recording area in the predetermined direction. A recorded clock area is provided in advance, and reading of the clock signal recorded in the clock area along the predetermined direction is started, and after the frequency of the read clock signal exceeds a predetermined value, information is stored in the recording area. Record. The invention according to claim 3 provides a method for recording information along a predetermined direction in a recording area of a magnetic recording section provided on a photographic film, by applying a clock signal in advance to the recording area of the magnetic recording section along a predetermined direction. and starts reading the clock signal recorded in the recording area along the predetermined direction, and after the frequency of the read clock signal reaches a predetermined value or more, overwrites the pre-recorded clock signal. Information is recorded in the recording area.

According to the first aspect of the invention, a clock area in which a clock signal is recorded is provided at least upstream in a predetermined direction of a recording area in which information is recorded along a predetermined direction. When the signal recorded in the clock area is read along a predetermined direction, the frequency of the read clock signal changes depending on the transport speed. That is, when the transport speed is high, the signal frequency is high, and when the transport speed is low, the signal frequency is low. Therefore, the transport speed of the photographic film can be easily detected by reading the clock signal using a magnetic system or the like for recording information in the magnetic recording section or reading information recorded in the magnetic recording section. . Therefore, there is no need to newly provide a detection means for detecting the transport speed of the photographic film, and since there is no need for a track to record only the clock signal, there is no need to provide a magnetic head dedicated to reading the clock signal, and the configuration can be simplified. It can be done easily. Note that the clock area in which the clock signal is recorded is not limited to the upstream side of the recording area in the predetermined direction, and the clock signal may also be recorded in the recording area. In the invention according to claim 2, a clock area in which a clock signal is recorded is provided in advance in a magnetic recording section upstream in a predetermined direction of a recording area in which information is recorded along a predetermined direction, and Reading of the recorded clock signal is started, and information is recorded in the recording area after the frequency of the read clock signal becomes equal to or higher than a predetermined value. The frequency of the read clock signal corresponds to the conveyance speed; when the conveyance speed is high, the frequency is high, and when the conveyance speed is low, the frequency is low. Therefore, by recording information after the conveyance speed increases and the frequency reaches a predetermined value or more, information can be reliably recorded in the magnetic recording section. In the invention according to claim 3, a clock signal is previously recorded along a predetermined direction in a recording area in which information is recorded along a predetermined direction, and the clock signal recorded in the recording area along the predetermined direction is read. After the frequency of the clock signal read at the start reaches a predetermined value or higher, information is recorded in the recording area by overwriting the previously recorded clock signal. As a result, in addition to the effect of claim 2, for example, when transporting a photographic film and recording information, the transport speed of the photographic film may increase more slowly than usual for some reason, and the arrangement of recording means such as a magnetic head may occur. Even if a predetermined transport speed at which information can be recorded is reached after the clock region of claim 2 passes through the set portion, the information is recorded in the recording area after the transport reaches the predetermined transport speed. Information can be recorded more reliably. Note that in the inventions of claims 1 to 3, information may be recorded in the recording area by transporting the photographic film, or by moving a recording means such as a magnetic head while the photographic film is stopped. You may go.

Embodiment FIGS. 1 and 2 show a negative film 10 according to this embodiment. The negative film 10 has an emulsion layer 14 provided on the upper surface of a transparent base 12 (FIG. 2), so that an image can be recorded by exposure. Also, transparent base 1
A magnetic recording layer 16 coated with a transparent magnetic material is provided on the lower surface of FIG. As shown in FIG. 1, this magnetic recording layer 16 is formed along the longitudinal direction of the negative film 10 outside the range of the image frame 10A of the negative film 10. 1
Tracks S1 and S2 where 0A is not recorded and tracks T1 and T provided corresponding to each image frame 10A
It is composed of 2. One perforation 11 is provided at the leading end of the tracks S1 and S2 and at the leading end of each track T1 and T2, each corresponding to the image frame 10A. Also, negative film 10
A plurality of perforations 13 are provided at the leading end of the negative film 10 so that the negative film 10 can be hooked onto the claws of a sprocket (not shown) and pulled out. Tracks S1 and S2 are areas for recording necessary information for each negative film 10, and tracks T1 and T2 are areas for recording necessary information for each image frame 10A. Each track of the magnetic recording layer 16 includes an area inputted during manufacturing of the negative film 10, an area inputted by a camera for photographing, and an area inputted by a DPE.
It is divided into an area for input in the store, an area for input in the lab, and an area for users to freely input, and these areas will be explained in detail below. (Track S1) As shown in FIG. 3, the track S1 according to the present embodiment has a total length of 50 mm, and the 3 mm portion at the tip and end thereof is used as clock regions 18 and 20,
The clock signal is recorded in a state where no image has been taken, that is, at the manufacturing stage. The clock areas 18 and 20 are used to detect the transport speed of the negative film 10 in a process (described later) in which information is recorded in a recording area sandwiched between the clock areas 18 and 20. Note that the negative film 10 is housed in a cartridge 206 (see FIG. 8), and in a normal camera, the negative film 10 is pulled out from the cartridge 206 and photographed while being conveyed in the direction shown by the arrow in FIG. 3, and information is stored in the recording area. Record. In this case, the conveyance speed is detected using the clock area 18 on the upstream side of the recording area in the conveyance direction. Also, depending on the type of camera, after all the negative film 10 is pulled out from the cartridge 206 and wound onto a spool or the like, the negative film 10 is rewound and stored in the cartridge 206, that is, in the opposite direction to the direction shown by the arrow in FIG. In some cases, information is recorded in the recording area by photographing while being conveyed in the direction of (so-called prewind). In such a case, the conveyance speed is detected using the clock area 20 located upstream of the recording area in the conveyance direction. Next to the clock area 18, there is a first STX area 22 where a start signal is recorded, a DPE input area 24 where information is recorded at a DPE shop where the user requests development of the photographed negative film 10, and an end signal. A first ETX area 26 for recording and an ECC area 28 for recording a first error correction signal are sequentially provided. Further, the second STX region 32, D
PE input area 34, second ETX area 36, second EC
A C area 38 is set. Furthermore, a third STX area 42 , a camera input area 44 , a third ETX area 46 , and a third ECC area 48 are arranged on both sides of the second blank section 40 .
is set and is continuous to the clock region 20 at the end. Note that the first STX area 22, the first ETX area 26, the second STX area 32, the second ETX area 36,
The third STX area 42 and the third ETX area 46 have a size of 2 bytes, and information specifying each area is recorded in advance. (Track S2) Next, as shown in FIG.
2 has a total length of 50 mm, and the tip and end are 3 m.
The m minutes are designated as clock regions 50 and 52, and like the clock regions 18 and 20, clock signals are recorded in advance. Next to the clock region 50, the first STX region 5
4. DX area 56 where the DX code is input, first ET
An X area 58 and a first ECC area 60 are set. In addition, a second STX area 64 with the blank part 62 in between,
Lab input area 66, second ETX area 68 and second E
A CC region 70 is set, and the terminal clock region 52
It is continuous. Note that the first STX area 54, the first
ETX area 58, second STX area 64, second ET
The size of the X area 68 is also 2 bytes, and information specifying each area is recorded in advance. (Track T1) As shown in FIG. 5, the total length of track T1 is 36 m, which is the same as the longitudinal dimension of image frame 10A.
m, and 3 mm at the tip and end is the clock area 7
2 and 74, and like the clock areas 18 and 20, a clock signal is recorded in advance. clock region 7
2, the STX area 76, camera input area 78, 8
0, an ETX area 82 and an ECC area 84 are set, and are continuous with the clock area 74 at the end. The size of the STX area 76 and ETX area 82 is also 2 bytes, and information specifying each area is recorded in advance. (Track T2) As shown in FIG. 6, the track T2 has a total length of 36 mm like the track T1, and 3 mm at the tip and end thereof are used as clock regions 86 and 88, and the clock regions 86 and 88 are used for clock signals as described above. is recorded in advance. Next to the clock region 86, the first STX region 9
0, DX area 92, first ETX area 94 and first E
A CC area 96 is set. Further, a second STX area 100, a laboratory input area 102, a second ETX area 104, and a second ECC area 106 are set with the first blank section 98 in between. Furthermore, the second blank section 1
08, a third STX area 110, a user input area 112, a third ETX area 113, and a third ECC area 114 are set, and are continuous to the terminal clock area 88. First STX area 90, first ETX area 94, second STX area 100, second ETX area 10
4. Third STX area 110, third ETX area 113
The size of each area is 2 bytes, and information specifying each area is recorded in advance. As shown in Figure 7, the size of each ECC area is ETX in the normal conveyance direction.
The size of the first EC is 20% of the size of the data area located upstream across the area, and as shown in FIG.
The size of the C area 28 is the data area (D in track S1).
It is assumed to be 20% of the size of the PE area 24). In the track S2 of the negative film 10 formed in this way,
At the manufacturing stage, lot numbers are determined as shown in Table 1. is binarized using the 8-bit ASCII code and inputted in advance. Track T1 also includes ISO sensitivity, negative/positive, number of sheets, manufacturer, and frame number as shown in Table 1. has been entered in advance.

[Table 1] FIG. 8 shows a camera 200 and a photo printing apparatus 202 according to this embodiment. The camera 200 is loaded with a cartridge 206 in which the negative film 10 is wound onto a spool 204 and stored therein. The negative film 10 is conveyed by the driving force of the motor 250 shown in FIG.
It is wound up in 4. As shown in FIG. 9, motor 250 is connected to a driver 254. Driver 254 is connected to control circuit 256. Further, a voltage from a battery (not shown) set in the camera 200 is applied, and a driving voltage is supplied to the motor 250 in response to an instruction from the control circuit 256 to transport the negative film 10. Inside the camera 200, a magnetic head 208 is provided corresponding to each track of the magnetic recording layer 16 of the negative film 10 (see also FIG. 8). The magnetic head 208 is connected to the magnetic recording layer 16
It is possible to write information to the magnetic recording layer 16 and read information recorded on the magnetic recording layer 16. The magnetic head 208 is connected to a control circuit 256 and writes information supplied from the control circuit 256 to the magnetic recording layer 16 .
The information read from is output to the control circuit 256. Also,
The control circuit 256 includes an optical system 2 consisting of a shutter, a lens, etc.
58 and controls the operation of the optical system 258 to record an image on the negative film 10. Note that in the camera 200 of this embodiment, once the cartridge 206 is set, all the negative film 10 is pulled out from the cartridge 206 and wound onto the spool 206, and then the negative film 10 is rewound and taken while being stored in the cartridge 206. It uses a prewind method that performs Further, after photographing, information regarding the photographed image is input from the optical system 258. Further, the camera 200 is provided with an operation section 210, through which predetermined information is input by manual operation. The control circuit 256 records predetermined information input from the optical system 258 and the operating section onto the track via the magnetic head 208 when the negative film 10 is conveyed by the motor 250 (see Table 2).

[Table 2] After photographing, the negative film 10 is rewound again into the cartridge 206, and then taken out from the camera 200.
Brought to DPE store. In this DPE shop, the negative film 10 is pulled out from the cartridge 206 in a darkroom, information as shown in Table 3 is recorded on tracks S1 and S2 based on the user's order, and then sent to the laboratory. In the laboratory, after the negative film 10 is developed, it is placed in a predetermined position in the photographic printing device 202 .

[Table 3] The photo printing device 202 has a light source 218 that is irradiated during printing.
A negative carrier 220 is disposed on the optical axis. The negative carrier 220 is provided with a drive roller (not shown) that is rotated by the driving force of a drive unit 224 connected to the control device 222, so that the negative film 10 is conveyed in the direction of arrow A in FIG. It has become. Further, the negative carrier 220 is provided with a solenoid 226.
In response to a signal from the control device 222, the negative film 10 can be clamped and pressed to the printing position. CMY filters 228 are interposed between the light source 218 and the negative carrier 220, and are moved along the optical axis according to the exposure amount of each color. The light beam transmitted through the negative film 10 is irradiated onto the photographic paper 232 through the lens 230, and an image is printed onto the photographic paper 232. A shutter 234 is interposed between the photographic paper 232 and the lens 230, and is retracted from the optical axis during exposure in response to a signal from the control device 222. Negative film 1
A reading head 236 is disposed upstream of the negative carrier 220 on the transport path of the camera 2.
The information recorded in the recording head 208 of 00 is read. The control device 222 is provided with a memory for recording information read by the reading head 234. Further, a magnetic head 238 for writing and reading is arranged downstream of the negative carrier 220, and information (information shown in Table 4) is recorded when the negative film 10 is subjected to the printing process by the printing device 202. It has become so.

[Table 4] Note that at the DPE shop, the information shown in Table 5 is also input into the developed negative film 10 finished in the laboratory. In this case, the developed negative film 10 can be worked in a bright room.

[Table 5] The operation of this example will be explained below. First, the photographing and information recording processing in the camera 200 will be explained with reference to the flowchart of FIG. In step 200, it is determined whether the cartridge 206 is loaded. camera 200
When the cartridge 206 is loaded, this determination is affirmed and the process moves to step 302. In step 302, the negative film 10 is pulled out from the cartridge 206 and wound onto the spool 252. In the next step 304, it is determined whether or not photography has been performed. When a shutter switch (not shown) of the camera 200 is turned on, photography is performed, and the control circuit 256 controls the optical system 258 to expose an image onto the negative film 10. As a result, the determination in step 304 is affirmed. In the next step 306, the motor 250 is driven via the driver 254 to start transporting the negative film 10. Note that the transport direction at this time is negative film 1.
The control circuit 256 controls the driver 254 so that the conveying speed of the negative film 10 gradually increases as shown in FIG.
The drive of the motor 250 is controlled via the. Step 30
In step 8, it is determined whether a clock signal has been detected. When the conveyance of the negative film 10 is started, the magnetic head 208 reads the information recorded on the magnetic recording layer 16, and the control circuit 25 reads the information recorded on the magnetic recording layer 16.
Output to 6. When the clock region 74 of the track T1 corresponding to the image frame reaches the location where the magnetic head 208 is provided, the magnetic head 208 outputs a clock signal. When the clock signal is output from the magnetic head 208, the determination in step 308 is affirmed. In the next step 310, it is determined whether the frequency of the clock signal is greater than or equal to a predetermined value. The clock signal output from the magnetic head 208 changes as shown in FIG. 12 as the conveying speed of the negative film 10 increases. That is, the period becomes gradually shorter as T1, T2, and T3, and the frequency, which is the reciprocal of the period, gradually increases in value. Until this frequency exceeds a predetermined value, the determination in step 310 is negative, and in step 312 it is determined whether the clock region has passed through the location where the magnetic head 208 is disposed. While the clock signal is being output from the magnetic head 208, the determination in step 312 is negative, and step 3
Return to 10. When the frequency of the clock signal output from the magnetic head 208 exceeds a predetermined value, the determination in step 310 is affirmed, and the process proceeds to step 314. Step 3
14, information from items 6 to 17 in Table 2 regarding the photographed image frame is displayed in the camera input area 78 of track T1 (excluding items 16 b and 16 f).
Record. When recording is completed, conveyance of the negative film 10 is stopped in step 316. In step 318, it is determined whether or not the number of images taken on the negative film 10 has been completed, for example, whether or not the number of images taken on a 12-shot negative film has been taken 12 times. If the determination at step 318 is negative, the process returns to step 304, and steps 304 to 318 are repeated until the determination at step 318 is affirmed, and images corresponding to the number of frames of the negative film 10 are photographed, and information regarding the photographed images is obtained. is recorded on track T1. Note that if the voltage of the battery set in the camera 200 decreases, sufficient driving voltage will not be supplied to the motor 250, and the conveyance speed of the negative film 10 will decrease to the speed V at which information can be recorded on the magnetic recording layer 16 (Fig. (see 11). In this case, the frequency of the clock signal output from the magnetic head 208 does not exceed the predetermined value, and the determination in step 312 is affirmed. In this case, an alarm prompting battery replacement is issued in step 320, and the process is terminated. If the determination in step 318 is affirmative, step 3
22, and in step 322, information is recorded on the track S1 in the same manner as above. That is, in step 322, conveyance of the negative film 10 is started again, and in step 324, it is determined whether or not a clock signal has been detected. When the clock region 20 of the track S1 provided for each negative film reaches the location where the magnetic head 208 is arranged and a clock signal is detected, the magnetic head 208 is moved in step 326.
It is determined whether the frequency of the clock signal output from the magnetic head 208 is greater than or equal to a predetermined value, and the determination in step 326 is repeated until the clock region passes through the location where the magnetic head 208 is disposed. If the determination in step 326 is affirmative, in step 330 the negative film 1 is placed in the camera input area 44 of track S1.
The information of item 16 b and item 16 f in Table 2 regarding 0 is recorded. In the next step 332, the entire negative film 10 is accommodated in the cartridge 206 and conveyance is stopped, thereby terminating the process. Further, if the voltage of the battery set in the camera 200 decreases and the negative film transport speed does not increase to the magnetic recording speed V, the frequency of the clock signal does not exceed the predetermined value and the determination in step 328 is affirmative. be done. In this case, an alarm prompting battery replacement is issued in step 334, and the process is terminated. camera 1
After shooting at 0 is completed, the spool 2 of the cartridge 206
The negative film 10 re-wound at 04 is brought to the DPE store by the user. At the DPE shop, the negative film 10 is pulled out from the cartridge 206 in a dark room, and the information shown in Table 3 is recorded in the DPE input area 24 of track S1. Regarding recording of information at this time, similarly to steps 306 to 318 in the flowchart of FIG. record when The negative film 10 received at the DPE store is transported to the laboratory and developed, and then, in the case of simultaneous printing, sent to the photo printing device 2.
02 is loaded into a predetermined position. When the negative film 10 is pulled out from the loaded cartridge 206 and conveyed by the drive unit 224 of the negative carrier 220, during this conveyance, the magnetic recording layer 16 is read by the reading head 236 by the recording head 208 of the camera 200 and by the recording device of the DPE store. The information recorded in is read. In the lab,
Based on the read information, printing conditions such as exposure amount are set, and each image frame 10A is sequentially positioned at a printing position, and printing processing is performed. Here, the laboratory input area 66 of the track S2 provided at the leading end of the negative film 10
, the negative carrier 220 is moved while the negative film 10 is being conveyed.
Information other than item 28 in Table 4 is recorded by a recording head 238 located downstream of the recording head 238 . Regarding recording of information at this time, step 3 of the flowchart in FIG.
Similarly to steps 06 to 318, it is detected whether the frequency of the detected clock signal is equal to or higher than a predetermined frequency, and if it is determined that the frequency is equal to or higher than the predetermined frequency, recording is performed. In addition, in the laboratory input area 102 of track T2 of each image frame 10A, item 28 (density correction value at printing,
(color correction values, etc.) is recorded. Regarding recording of information at this time, it is detected whether the frequency of the detected clock signal is equal to or higher than a predetermined frequency, and if it is determined that the frequency is equal to or higher than the predetermined frequency, recording is performed. Here, photographic paper 23
2. In the process of verifying the baked finish state, NG
If it is determined that this is the case, reprinting will be performed, but the frame number and correction value of the reprinted image frame 10A on the negative film 10 at this time are sent to each laboratory input area 66, 102 of the track S2 or track T2. By recording, the printing device 202 can perform optimal reprinting processing simply by reading this reprinting information. The developed negative film 10 and the photographic paper 232 that has been developed after printing are D.
Returned to PE store. At the DPE store, DP of truck S1
The information shown in Table 5 is recorded in the E input area 24 and returned to the user. Regarding recording of information at this time, it is detected whether the frequency of the detected clock signal is equal to or higher than a predetermined frequency, and if it is determined that the frequency is equal to or higher than the predetermined frequency, recording is performed. The user can arbitrarily record the information in item 18 of Table 2 into the user input area 112 in track T2 of each image frame 10A. This recording can be performed by operating the operating unit 210 provided on the camera 200. In this way, in this embodiment, the track S
1, S2, T1, and T2, each of which has a clock area in which a clock signal is recorded in advance, can easily detect the transport speed of the negative film 10.
The configuration can be simplified without the need to newly provide a detection means for detecting the conveyance speed of the photographic film or a magnetic head dedicated to reading a clock signal. Further, since information is recorded on the magnetic recording layer 16 after the frequency of the clock signal output from the magnetic head 208 becomes equal to or higher than a predetermined value, information can be reliably recorded on the magnetic recording layer 16. In addition, since a clock area is provided at the leading and trailing ends of each track, the conveyance speed can be detected using the clock area, regardless of whether the camera taking the image is a normal camera or a pre-wind camera. . Furthermore, since various information as described above is recorded in the magnetic recording layer 16 of the negative film 10 in each process, information is smoothly transmitted between each process, improving work efficiency. In this embodiment, clock areas in which signals of a predetermined frequency are recorded are provided at the leading and trailing ends of each track, but clock signals may be recorded in the entire area of each track. As an example, as shown in FIG. 13A, a clock signal is recorded in the entire area of the track T1, and information is recorded after the frequency of the detected clock signal reaches a predetermined value or more. As a result, recording of information is normally started from the positions shown in FIGS. 13(A) and 13(B). However, due to a drop in battery voltage, etc., the transport speed of the photographic film 10 increases more slowly than usual, and the frequency of the detected clock signal does not exceed a predetermined value even if the above-mentioned position passes through the location where the magnetic head 208 is disposed. In this case, Fig. 13 (
As shown in B), recording of information is started from the downstream side in the transport direction from the normal starting position, and the recorded clock signal is overwritten to record the information. Thereby, information can be recorded more reliably even when the battery voltage drops to some extent. In addition, in this embodiment, the magnetic head 208
If the frequency of the clock signal output from the battery does not exceed a predetermined value, an alarm is issued to prompt battery replacement, but the present invention is not limited to this.
For example, a clock signal output from a magnetic head may be sampled, and information may be output to the magnetic head 208 in synchronization with the frequency of the sampled clock signal. Thereby, even if the battery voltage drops, information can be recorded in the same way as when the battery does not appear to have dropped. Furthermore, the rotational speed of the motor 250 can be controlled to be constant using the clock signal output from the magnetic head 208.

As described above, in the invention as set forth in claim 1, since a clock area in which a clock signal is recorded in advance is provided in the magnetic recording section upstream in a predetermined direction of the recording area in which information is recorded, This has an excellent effect in that the film transport speed can be easily detected. In the invention according to claim 2, reading of the clock signal recorded in the clock area along a predetermined direction is started, and information is recorded in the recording area after the frequency of the read clock signal becomes equal to or higher than a predetermined value. Therefore, an excellent effect can be obtained in that information can be reliably recorded in the magnetic recording section of the photographic film. In the invention according to claim 3, after the reading of the clock signal recorded in the recording area along a predetermined direction is started and the frequency of the read clock signal becomes equal to or higher than a predetermined value, the pre-recorded clock signal is Since information is recorded in the recording area by overwriting, an excellent effect can be obtained in that information can be reliably recorded by the magnetic recording section of the photographic film.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a negative film according to this example.

FIG. 2 is a sectional view taken along line II-II in FIG. 1;

FIG. 3 is a plan view showing the area of track S1 in the magnetic recording layer.

FIG. 4 is a plan view showing the area of track S2 in the magnetic recording layer.

FIG. 5 is a plan view showing the area of track T1 in the magnetic recording layer.

FIG. 6 is a plan view showing the area of track T2 in the magnetic recording layer.

FIG. 7 is a schematic diagram showing the area width of each track.

FIG. 8 is a system diagram for recording and reproducing information according to the present embodiment.

FIG. 9 is a schematic block diagram showing a schematic configuration of a camera.

FIG. 10 is a flowchart for explaining the operation of this embodiment.

FIG. 11 is a diagram showing changes in conveyance speed from the start of conveyance of a negative film.

FIG. 12 is a waveform diagram showing a clock signal output from a magnetic head.

FIGS. 13A and 13B are plan views showing track areas for explaining another information recording method.

[Explanation of symbols]

10 Negative film (photographic film) 16
Magnetic recording layer (magnetic recording section) 18 Clock area 20 Clock area 50 Clock area 52 Clock area 72 Clock area 74 Clock area 86 Clock area 88 Clock area 200 Camera 208 Magnetic head 250 Motor 256 Control circuit

Claims (3)

[Claims] 1. A photographic film provided with a magnetic recording section and in which information is recorded along a predetermined direction in a recording area of the magnetic recording section, at least in the magnetic recording section upstream of the recording area in the predetermined direction. A photographic film characterized in that it is provided with a clock area in which a clock signal is recorded. 2. When information is recorded along a predetermined direction in a recording area of a magnetic recording part provided on a photographic film, a clock signal is recorded in a magnetic recording part at least on the upstream side of the recording area in the predetermined direction. A region is provided in advance, reading of a clock signal recorded in the clock region along the predetermined direction is started, and information is recorded in the recording region after the frequency of the read clock signal becomes equal to or higher than a predetermined value. Information recording method. 3. When recording information along a predetermined direction in a recording area of a magnetic recording section provided on a photographic film, a clock signal is previously recorded along a predetermined direction in the recording area of the magnetic recording section, After starting reading the clock signal recorded in the recording area along the predetermined direction and after the frequency of the read clock signal becomes equal to or higher than a predetermined value, overwriting the pre-recorded clock signal to write the clock signal in the recording area. An information recording method for recording information.