JPH0285843A - Transparent original illumination device - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention provides a transparent original illumination system which enables reading transparent originals such as slide films and OHP sheets by being installed on the original table of an image reading device. Regarding equipment.

(Prior Art) Conventionally, there is a device of this type as shown in FIG. 11. 100 is a transparent original illumination device, 113 is an image reading device, 103 is a projector, and 111 is a mirror unit. 106 is a transparent original such as a slide film or a 35-diameter negative film, and 101 is an illumination lamp. The light emitted from the illumination lamp 101 passes through the condenser lens 103a and illuminates the transparent original 106, and the transmitted light a passes through the projection lens 107 and is irradiated toward the mirror unit 111. This transmitted light is reflected by the reflection mirror 1 of the mirror unit 111.
04 and reaches the Fresnel lens 105, the transparent original 1 is placed on the original glass 102 of the image reading device gil 13.
A transmitted light image of 06 is formed. Reflection mirrors b and c in the image reading device 113 move and scan this optical image to the positions indicated by the broken lines, and the image is formed on the CGD 12 by the lens d, where it is read.

Further, in the case of a relatively large transparent original such as 8 inches XIO inches, the original is placed directly on the original glass 102 and subjected to transparent illumination.

Note that when the mirror unit) 111 is not used, the shaft 11
4 as the center, the mirror support member 110 is folded as shown by the two-dot chain line in the figure, the positioning pin 112 that positions the Fresnel support plate 71 is removed, and the mirror unit 111 is removed from the image reading device 113. Thereafter, the image reading device 113 is used as a reflective document reading device for reading a reflective document such as a drawing of the document 1 placed on the document glass 102 .

(Problem to be Solved by the Invention) However, since the Fresnel lens 105 has concentric or parallel straight fine J-grooves on its surface, when it is brought into close contact with the document glass 102, the fine grooves mentioned above are formed. This has the disadvantage that it disturbs the read image and adversely affects one image. As a way to prevent this, ■Fresnel lens 10
5. Provide a matte diffusion surface on one side of the entire surface. ■ Support the Fresnel lens 105 in the space above the original glass 102,
It is conceivable that the fine groove of the Fresnel lens 105 is located outside the focal range of the lens d on the image reading device 113 side.

However, when method (■) was adopted, the amount of transmitted light irradiated on the transparent original in the projector was reduced, making it difficult to read the image accurately, and when method (■) was adopted, the disturbance of the read image due to micro grooves was reduced. However, when reading the image of a large transparent original as described above, wrinkles, sagging, waving, etc. may occur due to local expansion and contraction due to the heat of the projection light and the curl of the transparent original, which may affect the read image. A new problem has arisen:

The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a transparent document illumination device that can prevent image distortion caused by the microgrooves of a Fresnel lens. Another purpose is to prevent the read image from being distorted due to the heat of the projection light, the curl of the transparent original, etc. when a relatively large transparent original is placed directly on the original glass and the image is read.

(Means for Solving the Problems) In order to achieve the above object, the present invention includes an irradiation unit that irradiates light from a light source onto a document glass of an image reading device, and a Fresnel lens supported in parallel with the document glass. In the transparent original illuminating device, a document pressing member is provided between the original glass and the Fresnel lens to bring the transparent original into close contact with the original glass.

(Function) The function of the present invention based on the above structure is that the read image is not disturbed by the minute grooves of the Fresnel lens, and that the large transparent original placed on the original glass is protected from the heat of the projection light and the irregularities of the original itself. , no deformation due to wrinkles or sagging.

(Example) Next, the present invention will be described based on an example shown in FIGS. 1 to 10.

In FIGS. 1 and 2, B is the document illumination device of the present invention, A is the main body of the image reading device, and AI is the operation panel. C is a projector placed on a stand Bl provided on image reading device A;
is a mirror unit.

1 is a slide film or a transmission original film such as a 35+S layer negative film, and 2 is an illumination lamp. The light emitted from the illumination lamp 2 passes through the condenser lens 3 and illuminates the original film 1, and the transmitted light 5 passes through the projection lens 4.
The light is irradiated onto the mirror unit C through the . Thereafter, the light 5 reaches the Fresnel lens 7 by the reflection mirror 6 of the mirror unit C, and a transmitted light image of the original film 1 is formed on the original glass 8 of the main body A of the image reading apparatus. The mirror unit) C is composed of a mirror support member 61 that supports the reflecting mirror 6, and a connecting plate 14 rotatably connected to one end of the mirror support member 61 via a shaft 62. Connecting plate 14 and stand B! are rotatably connected by a shaft B2. Reference numeral 7 denotes a Fresnel lens, and the Fresnel lens 7 is supported at a position above the document glass 8. Reference numeral 71 denotes a Fresnel support member that supports the Fresnel lens 7. One end of the Fresnel support member 71 is rotatably provided to the mirror support member 61 via a shaft 72, and the other end is rotatably provided to the link plate 15 via a shaft 73. Possibly supported.

A document holding member 13 is arranged between the Fresnel lens 7 and the document glass 8 so as to be in contact with the document glass 8.

The document holding member 13 is made of a transparent material and is supported by a holding member support 131. The document holding member 13 will be described in detail later.

Similarly to the Fresnel support member 71, one end of the holding member support member 13 is rotatably provided on the mirror support member 61 via a shaft 132, and the other end is rotatably supported on the link plate 15 via a shaft 133. There is.

For this reason, the mirror support member 61. Fresnel support member 71.
The presser plate support member 131 and the link plate 15 constitute a parallel link mechanism, and the handle 74 shown in FIG.
By lifting in six directions, the Fresnel lens 7 and document holding member 13 can be housed and held in the mirror supporting member 61 by a locking means (not shown) as shown by solid lines in FIG.

By using the parallel link mechanism as described above, the second
The distance h2 in the stored state shown in the third factor can be made smaller than the distance h1 between the Fresnel lens 7 and the document holding member 13 in the used state shown in the figure.

As shown in FIG. 1, the mirror support member 61 has rollers 17.
is rotatably attached via a shaft 171. Therefore, in FIG. 3, when mirror unit D is in the solid line state, by pushing in the direction of the arrow 18, the roller 17 rolls on the document glass 8, collides with the stopper B3 of the table B1, and is folded, as shown by the dashed line. . In this folded state, since the roller 17 is located to the right of the perpendicular line V passing through the axis 62, the roller 17 is moved in the direction of the arrow 18' due to the moment generated around the axis B2 due to the weight of the mirror unit) C. Since it is biased, it can stably maintain its folded state.

By placing the mirror unit in the folded state D', the main body A of the image reading apparatus can place a drawing of a document, etc. on the original glass 8, and can be used as a reflective original reading device using a light source.

By the way, if the user releases his/her hand when the mirror support member 61 is moved in the direction of the arrow 19 so that the roller 17 is positioned to the left of the perpendicular line V (for example, indicated by the broken line D'' in the figure), the mirror unit D The roller 15 is transferred due to its own weight and suddenly becomes the state shown by the solid line in the figure, and the shaft 62 shaft B and the mirror support member 6
There is a risk of damage due to severe impact force being applied to the 1st class.

Therefore, in this embodiment, a damper E is used to prevent the above-mentioned danger. One end of the damper E is rotatably connected via the shaft 63 of the mirror support member 61, and the other end is connected to the connecting plate 14 through the shaft 63. It is rotatably supported via 43. This damper E (7) mechanism will be explained based on FIG. 4.

4(a) shows the extension when the shaft 143 moves in the direction of arrow 20 with respect to the shaft 63, and FIG. 4(b) shows the shaft 143 with respect to the shaft 63.
43 indicates compression when moving in the direction of arrow 21.

Piston E2 in cylinder E1 is connected to piston rod E3
The piston rod E3 protrudes outside the cylinder EI via a seal E4. A minute orifice E5 is bored in the piston E2, and a valve E6 is disposed therein. Space G in cylinder El divided by piston E2
dregs are enclosed in l r G 2. When expanding (
In a), the gas in the space G2 flows as indicated by the arrow 22 and flows into the space G1 via the orifice E5, so that a damper effect is obtained due to the resistance when the gas passes through the orifice.

On the other hand, during compression (b), the position of the valve E6 changes opposite to that in (a), so the gas in the space G1 passes through the piston rod and moves to the space G2 as shown by arrow 23 without passing through the orifice E5. . For this reason, a damper E having a value of 0 or more, which has almost no damping effect, is used at the position shown in FIG. 1 and at an opposing position (not shown).

In Figure 3, the mirror unit) D is indicated by the broken line water D''.
When you release your hand at the position, the roller 17 rolls in the direction of the arrow 19. At that time, the damper E expands, so a damper effect is obtained.

? Reference numeral 4 designates an arm, one end of which is rotatably connected to the sleeve 63, and the other end slidably supported via a long hole 241 to the shaft 144 of the connecting plate 14. The arm 24 is also provided at an opposing position (not shown).

In the mirror unit) D, when the roller 17 rolls in the direction of the arrow 19, the mirror support member 61 moves relatively slowly to the left due to the damper effect of the damper E, and the long hole 241 of the arm 24 hits the shaft 144, i.e. , movement stops at the solid line state. At this position, the reflecting mirror 6 is adjusted to a predetermined angle.

By using the damper E as described above, the shaft 62.
Axis B2, axis L14. This prevents severe impact from being applied to the mirror support member 61 and the like. Moreover, the variation in the angle of the reflecting mirror 1 when the mirror support member 61 is opened is also reduced. (According to experiments, the repeat angle variation of the reflecting mirror 6 is on the order of several minutes to several tens of minutes. When the mirror support member 61 is returned to the storage position D', the damper E is compressed, so the damper E does not work. It can be stored smoothly without any resistance.

In this embodiment, two dampers E are used, one each on the front side and one on the back side, but the damper E may be used only on either the front side or the back side.

FIG. 5 shows a film carrier 101. FIG.

When projecting a 35 mm film, slide film, etc. using the transparent original illumination device of this embodiment, first, as shown in FIG.
, l0IB 9 Next, this film carrier 101 is inserted into the projector B as shown in FIG.
into the carrier hole 102, and place the desired frame on the optical axis. After that, the operation panel A of the image reading device main body A
By pressing the I button and making a predetermined input, an image reading operation similar to that described in the prior art example is performed.

By the way, in this embodiment, the Fresnel lens 7 is supported above the original glass 8, and the fine groove of the Fresnel lens 7 is positioned outside the focal range of the lens 11 of the main body A of the image reading apparatus. This prevents the adverse effects (disturbance of images) caused by the grooves of the lens 7.

In this example, in addition to 35m @ film and Kokang slide film, we used 8 inch x 10 inch, 4 inch
Large transparent originals such as inch x 5 inches or OHP
It can be read by transmitting and illuminating a film, etc.

FIG. 6 is a perspective view illustrating the case of transmitting illumination of the above-mentioned relatively large transparent document.
Manuscript set up in! The placement reference 81 is a reference for placing an original when reading a normal reflective original (document 2 drawing, etc.).

When reading the transparent original 25 with the image reading device main body A, first, the transparent original reference sheet 2 is placed against the original storage reference 81.
6 and then place the transparent original reference sheet 26
The transparent original 25 is positioned with respect to the placement reference 261. The transparent original reference sheet 26 may be, for example, an L-shaped sheet as shown in FIG. Can be used.

FIG. 8 is a side sectional view of the vicinity of the document holding member 13. (
(a) is when there is no transparent original 25, and (b) is when transparent original 25 is not present.
The original holding member 13 shown in FIG. 1 is placed on the transparent original reference sheet 26, and is supported with play 134 with respect to the holding member support 131. For this reason, (a)
In the case of (b), the original holding member 13 is placed in close contact with the original glass 8, but in the case of (b), the thickness of the transparent original 25 is absorbed by the backlash 134 of the original holding member 13, and the transparent original 25 is placed in close contact with the original glass 8. is pressed against the original glass 8 by the original weight of the original pressing member 13. In this way, by using the original pressing member 13, the transparent original 25 is sagged on the surface.

The document glass 8 can be placed without causing waving or other placement defects.
It is placed in close contact with the top.

FIG. 9 is a plan view when the transparent original 25 is placed on the original glass 8, and (a) is a plan view of the transparent original 25 placed on the original glass 8. 251 is shown.

Further, (b) shows a case where a relatively small film such as a 4 inch x 5 inch photographic film is placed as the transparent original 252.

In (a), when the transparent original reference sheet 26 applied to the large transparent original 251 is used, when the large transparent original 251 is placed, the center of the Fresnel lens 7 (cross 71 in the figure) will be approximately at the center of the transparent original 251. It's arranged like this.

In this state, when the small transparent original 252 (indicated by chain lines in the figure) is positioned M and placed with respect to the reference of the transparent original reference sheet 26, the center 71 of the Fresnel lens 7
It will be located far away from the center of 2. Therefore, at a position away from the center 71 of the Fresnel lens 7, the light intensity distribution is uneven, and this adverse effect is likely to appear.
As shown in b), by using the second transparent original reference sheet 26' suitable for the small transparent original 252 and arranging it so that the center 7e of the Fresnel lens 7 is near the approximate center of the transparent original 251. , the above negative effects can be eliminated.

FIG. 10 is a perspective view of the mirror support member 61. A sheet pocket 67 is provided on the back side of the mirror support member 61, and can store, for example, a sheet N such as an original film or a semi-transparent original X sheet. As a result, various sheets necessary for the transparent original illumination device, such as original film and transparent original reference sheet, can be prevented from scattering and can be easily stored.

In the above embodiment, the transparent original illumination device is
Although the present invention is attached to an image reading device that reads an image using OD, the image reading device to which the present invention can be applied is not limited to the one described in L, but also a copying machine that forms a light image from a document onto a photoreceptor. It can also be used in image forming apparatuses such as the following.

(Effects of the Invention) Since the present invention is configured as described above, even though the Brenell lens is provided above the original glass, the transparent original is brought into close contact with the original glass, so that the transparent original does not wrinkle. This has the effect of preventing the read image from being disturbed due to waving or the like.

[Brief explanation of the drawing]

1 to 10 show an embodiment of the present invention, and FIGS. 1 and 6 are perspective views of the entire transparent original illumination device, FIG.
Figure 3 is a front view, Figures 4 (a) and (b) are sectional views showing the operation of the damper, Figure 5 is a perspective view of the film carrier, and Figures 7 (a) and (b) are transparent views. A perspective view of the document reference sheet, FIGS. 8(a) and (b) are partially cutaway front views showing the document holding member, and FIGS. 9(a) and (b) are views of a transparent document placed on the document glass. A plan view, FIG. 10 is a perspective view of a mirror support member, and FIG. 11 is a front view showing a conventional example. Explanation of symbols 2...Light source (illumination lamp) 7...Fresnel lens 8...Original glass 13...Original holding member 25.
251, 252... Transparent original A... Image reading device main body C... Irradiation means (projector) Fig. (b) Fig. 10

Claims (2)

[Claims] (1) In a transmission document illumination device including an irradiation unit that irradiates light from a light source onto a document glass of an image reading device, and a Fresnel lens supported in parallel with the document glass, the document glass and the Fresnel lens are connected to each other. A transparent document illuminating device characterized in that a document pressing member is provided between the document sheets and the document glass to bring the transparent document into close contact with the document glass. (2) The transparent original illuminating device according to claim 1, wherein the original holding member is provided so as to be slidable along the direction of light irradiation from the light source.