JPH0455845A - Photographic printer - Google Patents

Abstract

PURPOSE:To simplify constitution and to provide the compact printer by providing a light intensity modulating means, such as liquid crystal panel, and changing the light transmission quantity for each of respective colors according to exposures. CONSTITUTION:A controller 16 determines the voltage control signal driving the respective cells 48 of R, G, B of the liquid crystal panel for each of the respective colors from the exposures for three colors by an exposure/voltage converting section 47 and outputs this voltage via a selector 48 to a driver 15. The driver 15 drives the respective cells 48 of the liquid crystal panel 13 with the prescribed voltage for each of the respective colors by this voltage control signal to obtain the prescribed light transmission quantity. Mechanical moving parts are eliminated and durability and reliability are improved in this way. In addition, the device constitution is simplified and the compact printer is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a photographic printer, and more particularly to a photographic printer in which a light quality adjustment section has a simple configuration.

[Conventional technology]

In a photo printer, each frame of negative film is photometered, the exposure amount is calculated based on the obtained full screen average density (LATD), etc., and the color filter setting position is determined based on this exposure amount, and the color filter is placed within the printing optical axis. is set to ensure proper color balance, etc., and then print exposure is performed.

[Problem to be solved by the invention]

However, the light quality adjustment type photo printer described above requires three color filters, a filter drive unit that inserts these into the optical axis, and a diffusion box that uniformly diffuses the printing light whose light quality has been adjusted by the color filters. is required. Furthermore, since the color filter has a movable part, the device configuration becomes complicated, and there are problems with durability and reliability. Furthermore, the above-mentioned diffusion box has a problem in that it is difficult to control the mixing ability in terms of design and manufacturing. Furthermore, it is difficult to make it compact and cost-effective due to the light quality adjustment section and diffusion box.

The present invention is intended to solve the above problems, and provides a photo printer that eliminates mechanically moving parts, improves durability and reliability, and allows for a simple and compact device configuration. The purpose is to provide.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a light source that illuminates a photographic film, and a matrix arrangement of minute electro-optic light valves that are provided between the light source and the photographic film and that change the amount of light transmitted. At the same time, the light intensity modulating means includes color filters of three primary colors arranged in a matrix in correspondence with each light valve, and means for controlling the amount of light transmitted through each light valve of the light intensity modulating means according to the amount of exposure. It is prepared. Further, in another invention, the light intensity modulation means is separated from the photographic film so that the pattern of minute color filters arranged in a matrix of the light intensity modulation means will not be imaged on the photosensitive material. It is something.

[Effect]

When the exposure amount is calculated based on the photometry result of the frame to be printed, the voltage to the light intensity modulation means, for example, the light valve corresponding to the three primary color filters of the liquid crystal panel, is adjusted according to this exposure amount, and the voltage is adjusted depending on the exposure amount. The amount of light transmitted is controlled so that the quality of light corresponds to the amount of exposure. As a result, printing exposure is performed with the optimum light quality for the frame to be printed.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

In FIG. 2, which schematically shows the configuration of a photographic printer, light from a lamp 10 is reflected by a reflector 11, then converted into parallel light by a light source lens 12, and is incident on a liquid crystal panel 13. Between the reflector 11 and the light source lens 12,
A heat shielding filter 14 is arranged to prevent the temperature of the liquid crystal panel 13 from rising due to heat from the light source 12.

The liquid crystal panel 13 is composed of a well-known active matrix liquid crystal display (LCD), in which each cell (light valve) is arranged in a matrix, and red (R), green ( G).

Blue (B) color filters are arranged in a matrix. In this embodiment, the number of cells of this liquid crystal panel 13 is 20X.
The liquid crystal panel 13 is controlled by a controller 16 via a driver 15, although the liquid crystal panel 13 is not limited thereto. The driver 15 changes the applied voltage for each R, G, and B cell based on a control signal from the controller 16, and changes the amount of light transmitted.

A diffusion plate 17 is disposed above the liquid crystal panel 13, and the light from the lamp IO whose light quality has been adjusted is sufficiently diffused by the liquid crystal panel 13 to illuminate the frame to be printed on the negative film 19. 19 is film carrier 2
Set to 0. As is well known, the film carrier 20 detects the frame position and places the frame to be printed at the print position.

The image of the frame to be printed is formed by a printing lens 23 onto a color paper 24 set at a printing position. A shutter 25 is arranged between the printing lens 23 and the color paper 24, and a shutter drive section 26
It is opened and closed by

Further, a half mirror 28 is arranged on the printing optical axis between the film carrier 20 and the printing lens 23, and branches the printing light to a photometry/monitoring system 30. The branched light passes through a lens 31 and a half mirror 32, and is focused on an image area sensor 33 for simulation and an image area sensor 34 for photometry (scanner). Incidentally, instead of the half mirror 28, a half prism may be used, or a movable mirror may be provided to be freely inserted and removed from the printing optical axis.

The image area sensor 33 for simulation captures a negative image of the frame to be printed, and sends this video signal to the monitor image processing section 36. As is well known, the monitor image processing unit 36 performs A/D conversion, negative/positive conversion one-tone correction, saturation correction, etc., and displays a monitor image simulating a finished print on the color CRT 37. The saturation correction not only corrects the difference between the spectral sensitivity of the color paper 24 and the spectral sensitivity of the image area sensor 33, but also performs color correction to display an image simulating this correction when inputting correction data. Input the correction data using controller 1.
The input density correction data and color correction data are displayed on the display 41 and are also processed by the image processing unit 36.
sent to.

The photometric image area sensor 34 performs three-color separation photometry on each point of the frame to be printed. This photometric signal is sent to the characteristic value calculation section 45. The characteristic value calculation unit 45 calculates LATD and other various characteristic values, and applies the calculated values to the exposure amount calculation unit 46.
send to The exposure calculation unit 46 calculates the exposure using a well-known exposure calculation formula and sends it to the controller 16.

When calculating the exposure amount, correction data input from the keyboard 40 is also used as necessary.

As shown in FIG. 1, the controller 16 converts the exposure amount of the three colors into the liquid crystal panel 13 using the exposure amount-voltage converter 47.
A voltage control signal for driving each of the R, G, and B cells 48 for each color is determined and outputted to the driver 15 via the selector 49. Using this voltage control signal, the driver 15 drives each cell 48 of the liquid crystal panel 13 with a predetermined voltage for each color to achieve a predetermined amount of light transmission. Furthermore, when the liquid crystal panel 13 is driven, the controller 16 opens the shutter 25 for a certain period of time via the shutter drive section 26 to print and expose the image of the frame to be printed on the negative film 19 onto the color paper 24 . The relationship between the exposure amount and the voltage applied to each cell of the liquid crystal panel 13 is determined in advance through experiments, etc., and a conversion table thereof is stored in the memory within the controller 16.

Furthermore, during photometry/monitoring, the controller 16 receives a voltage from the exposure amount-voltage converter 47 via the selector 49 in order to prevent the image area sensors 33 and 34 from becoming saturated due to excessive light amount and making photometry impossible. The control signal generator 50 is switched to send a voltage control signal in photometry mode to the driver 15. As a result, a predetermined voltage is applied to each cell 48 of the liquid crystal panel 13 for each color. Therefore, each cell has a predetermined amount of light transmitted, and the amount of light for each color from the lamp 10 is narrowed down corresponding to the image area sensor, so the amount of light can be adjusted to the dynamic range of each image area sensor 33, 34. I can do it. The voltage applied to each cell 48 for controlling the light intensity is determined in advance through experiments or the like, and is stored in the memory of the controller 16. In addition, the image area sensor 33
When the dynamic ranges of 34° are different, the applied voltage is determined for each sensor, and the liquid crystal panel 13 is first driven in accordance with the simulation sensor 33 to capture a negative image. Thereafter, the liquid crystal panel 13 is driven in accordance with the sensor 34 for photometry to perform photometry.

Next, the operation of this embodiment will be explained with reference to FIG. First, when the negative film 19 is set on the film carrier 20 and the frame advance key on the keyboard 40 is operated, the film carrier 20 transports the negative film 19 and sets the frame to be printed at the print position. This setting is performed by detecting the edges of the frames, as is well known. Next, the frame to be printed is illuminated by the lamp 10. At this time, the voltage control signal generator 50 of the controller 16 sends a control signal to the driver 15, the liquid crystal panel 13 is set to photometry mode, and the image area sensor 33
, 34, each cell 48 is driven to transmit a predetermined amount of light for each color.

Then, a negative image of the frame to be printed is captured by the imaging image area sensor 33, and this video signal is subjected to A/D conversion, negative/positive conversion, gradation correction, and saturation correction in the monitor image processing unit 36, and the finished print is processed. A simulated monitor image is displayed on the color CRT 37. When observing this monitor image and determining that density or color correction is necessary, each correction data is input using the keyboard 40. Each of the input correction data is sent from the controller 16 to the monitor image processing section 36, where correction processing is performed using each correction data, and the corrected monitor image is displayed on the color CRT 37.

Observe the monitor image, and if correction is required again, input correction data in the same manner. Furthermore, if this is acceptable, printing is started by operating the print key.

First, each correction data is determined by operating the print key, and based on this correction data and various characteristic values, the printing exposure amount for each color is calculated using a well-known exposure calculation formula, and this is sent to the controller 16. The controller 16 sends a voltage control signal for each cell 48 of the liquid crystal panel 13 to the driver 15 based on the printing exposure amount for each color. As a result, the driver 15 drives each cell with a predetermined voltage, so the liquid crystal panel 13 is driven in an exposure mode, and each cell 48 transmits a predetermined amount of light. Then, since the shutter 25 is opened by the shutter drive section 26 for a predetermined period of time, printing exposure is performed. Thereafter, each frame is printed and exposed in the same manner.

Note that in the above embodiment, the light intensity modulation means is the liquid crystal panel 1.
3, but PLZT may also be used. Additionally, if the variable increments (resolution) of the light transmission amount of each cell cannot be adjusted to a sufficiently fine level, the printing exposure amount can be controlled at a fine level by sequentially decreasing the number of driven cells. . In this case, the number of cells is increased to reduce the influence of the thinning drive. In addition, by adjusting the cell ON time for each color, exposure control can be performed at a more detailed level.

In addition, the above embodiment is a printer for a small laboratory that performs negative verification for each frame before printing. The present invention can also be implemented in a large laboratory type printer.

Further, in the above embodiment, the diffusion plate 17 is arranged between the liquid crystal panel 13 and the negative film 19 to prevent the pattern of each cell of the liquid crystal panel 13 from being imaged on the photosensitive surface of the color paper 24. However, instead of this, the diffusion plate may be omitted and the liquid crystal panel may be separated from the negative film to reduce the influence of the pattern of each cell of the liquid crystal panel.

〔Effect of the invention〕

As explained above, according to the present invention, a light intensity modulation means such as a liquid crystal panel is provided, and the amount of light transmission is changed for each color according to the amount of exposure. There is no need to provide a color filter, a filter drive unit for setting the color filter within the printing optical axis, a diffusion box, etc., and the configuration can be made simple and compact. Furthermore, since there are no mechanically moving parts, durability and reliability can be improved.

Further, the light intensity modulation means is placed apart from the photographic film,
By setting the printing lens at a defocused position, it is possible to reduce the influence of the pattern of each cell of the light intensity modulating means and improve print quality.

[Brief explanation of the drawing]

FIG. 1 is a functional block diagram of the main parts of a photographic printer according to the present invention. FIG. 2 is a schematic diagram showing the configuration of a photo printer. FIG. 3 is a flowchart showing the control procedure of the photo printer. 10 ・ ・ ・ 13 ・ ・ ・ 15 ・ ・ ・ 16 ・ ・ 19 ・ ・ ・ 33.34 48 ・ ・ ・ Lamp LCD panel driver controller Negative film... Image area sensor cell.

Claims (2)

[Claims] (1) In a photographic printer that prints and exposes an image recorded on a photographic film onto a photosensitive material, a light source illuminates the photographic film, and a microscopic light source is installed between this light source and the photographic film and changes the amount of light transmitted. a light intensity modulation means in which electro-optical light valves are arranged in a matrix, and color filters of three primary colors are arranged in a matrix in correspondence with each light valve; and each light valve of the light intensity modulation means in accordance with the amount of exposure. A photographic printer comprising means for controlling the amount of light transmitted through the printer. (2) In a photographic printer that prints and exposes an image recorded on a photographic film onto a photosensitive material, a light source that illuminates the photographic film, and a light source provided between this light source and the photographic film, separated from the photographic film, so that the light transmits A light intensity modulation means has minute electro-optic light valves whose amount changes are arranged in a matrix, and color filters of three primary colors are arranged in a matrix in correspondence with each light valve, and the light intensity is adjusted according to the exposure amount. A photographic printer comprising means for controlling the amount of light transmitted through each light valve of the modulating means.