JPH11142964A - Microfilm retrieval device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain the miniaturization of a device and to reduce the number of parts by unnecessitating a light source lamp exclusively for an optical fiber and a diffusing plate at a microfilm retrieving device discriminating the existence of a frame by the density change of microfilm in a running direction. SOLUTION: This device is provided with a pair of optical fiber holding blocks 100 and 102 opposed to both faces of the microfilm by crossing the microfilm in a width direction, the optical fibers 104 and 106 which are penetrated and held through/by both blocks and whose end faces are opposed to each other by holding the microfilm 26, a light source leading light to the optical fiber held by one block, an optical sensor 108 detecting the light quantity of the light made incident on the optical fiber held by the other block, and a binarizing part 110 binarizing the output of the optical sensor 108 and a retrieving part 116 executing the retrieval of the frame by discriminating the existence of the frame based on a binary signal, and the light source is formed of the lamp 54 of the light source to project the image of the microfilm, a light- shielding plate directly shielding the light made incident on the light source side end face of the optical fiber on the side of the light source from the lamp 54 and a reflector 56 leading the reflected light of the lamp 54 to the optical fiber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microfilm search apparatus for judging the presence or absence of a frame from a change in density of a microfilm in a running direction.

[0002]

2. Description of the Related Art In order to search for microfilms,
A device is known in which a search mark (blip) is attached to each frame at a position that does not overlap the traveling locus width of the frame, and the blip is detected and searched.

On the other hand, it has been considered that a search is performed by detecting the presence or absence of a frame instead of the blip. That is, a density sensor is provided within the width of the traveling locus of a frame, and the presence or absence of a frame is determined from a change in film density detected by the density sensor.

[0004]

In order to detect the presence or absence of a frame, the end faces of a pair of optical fibers are opposed to each other with the film interposed therebetween, and light incident on one of the optical fibers is guided to the film and transmitted through the film. It is conceivable that light is received by the other optical fiber and the amount of the received light is detected by an optical sensor.

In this case, it is desirable that the intensity of light emitted from one optical fiber toward the film is evenly distributed around an axis perpendicular to the film. For this purpose, it is necessary to homogenize the intensity distribution of the light incident on the optical fiber from the light source. Therefore, a milky white diffuser is interposed between the lamp and the end face of the optical fiber, and the light of the lamp is evenly diffusely reflected and scattered by the diffuser,
It is conceivable to make this scattered light incident on the optical fiber.

However, in this case, a light source lamp and a diffuser for an optical fiber are required, which causes a problem that the apparatus becomes large and the number of parts increases.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and eliminates the need for a light source lamp or a diffuser dedicated to an optical fiber, thereby miniaturizing the apparatus and reducing the number of parts. It is an object to provide a film search device.

[0008]

According to the present invention, an object of the present invention is to provide a microfilm search apparatus which determines the presence or absence of a frame based on a change in density in the running direction of a microfilm. A pair of opposing optical fiber holding blocks, an optical fiber whose one end face penetrated and held by both blocks is opposed to each other across a microfilm, and a light source for guiding light to the optical fiber held by one block. An optical sensor for detecting the amount of light incident on the optical fiber held in the other block, a binarizing unit for binarizing the output of the optical sensor, and determining the presence or absence of a frame based on the binarized signal. A light source for projecting a microfilm image, and a light source on the light source side from the lamp. A light shielding plate for blocking light directly incident on the light source side end face of the microfilm search device lamp reflected light, characterized in that it is formed by the reflection plate to guide the optical fiber is achieved by.

The two optical fiber holding blocks respectively hold one ends of a plurality of pairs of optical fibers facing each other with the film interposed therebetween at different positions in the film width direction, and converge the light source side ends of the plurality of optical fibers. To the lamp side. In this case, the presence or absence of a frame can be detected at a plurality of different positions in the width direction of the film. When a plurality of pairs of optical fibers are provided in this manner, the plurality of optical fibers held in the same optical fiber holding block are set to the same length, so that an optical fiber for detecting a frame at a plurality of positions on the film is provided. The conditions of each pair can be made identical.

[0010]

FIG. 1 is a view showing a use state of one embodiment of the present invention, FIG. 2 is a perspective view showing the inside of a scanner used here, FIG. 3 is a side view showing an arrangement of main parts of the scanner, and FIG. 5 is a perspective view showing a line sensor driving unit, FIG. 5 is a diagram showing a main part, and FIG. 6 is a diagram for explaining an arrangement of optical sensors.

In FIG. 1, reference numeral 10 denotes a computer main body, which includes a CPU and the like. Reference numeral 12 denotes a display means such as a CRT or a liquid crystal plate, and 14 denotes a keyboard, which are placed on a desk 16. Reference numeral 18 denotes a scanner housed under the desk 16, which incorporates the microfilm search device of the present invention. Reference numeral 20 denotes a printer placed beside the desk 16.

The scanner 18 has a cartridge insertion port 22 at an upper portion of the front surface thereof.
4 (see FIGS. 2 and 3), the image of the micro-roll film 26 having a width of 16 mm is read at a low density. The read image is subjected to predetermined image processing by a CPU or the like in the computer main body 10 and then displayed on the display unit 12.

This image reading is performed while the line sensor 96 described below is stopped and only the film 26 is running.
In the meantime, the display means 12 of the CRT displays the read image while changing it continuously in synchronization with the running of the film 26. Therefore, the display on the display means 12 moves in synchronization with the running of the film 26, and an image substantially similar to that projected on the screen can be displayed on the display means 12.

At the time of a manual search, the operator looks at the image on the display means 12 and instructs an output for an image that needs to be printed. Based on this output instruction, the scanner 18 sets the position of the frame to a correct position and reads the entire image with high-density image quality. This high-density image is printed out to the printer 20, stored in a memory such as a magneto-optical disk, or transferred to an external processing device.

At the time of automatic search, the address of the target frame is input from the keyboard 14. In this automatic search, a target frame is searched by detecting frames and counting the number of frames. This frame search is performed by using the determination result of the determination unit 112 described later indicating the presence or absence of the frame, and
16 is performed.

Next, the configuration of the scanner 18 will be described. The scanner 18 has a vertically long housing 28, and a supply-side reel drive unit 30 is provided above a front portion of the housing 28, and a take-up reel drive unit 32 is provided below the front portion. The supply-side reel drive unit 30 inserts the cartridge 2 into the cartridge insertion slot 22.
When the cartridge 4 is inserted, the cartridge 24 is automatically moved to engage the reel 24A with the rotating shaft. Further, the leading end of the film 26 is pulled out, sent downward, and guided to the take-up reel 32A of the take-up reel drive unit 32.

Here, as shown in FIGS. 2 and 3, the film 26 passes through the rear side of the gap between the reel drive units 30 and 32, that is, the rear side as viewed from the front of the housing 28. In FIG. 3, 34, 34,
36, 36 are guide rollers for the film 26. Accordingly, a space 38 is formed between the gap and the front panel 28A of the housing 28, and a light source unit 52 described later is accommodated therein.

The take-up reel drive section 32 has a drive belt 40 that runs in contact with the reel 32A as shown in FIG. This drive belt 40 is a guide roller 4
2, 44, a drive roller 46, an encoder 48, and a tension roller 50, and are driven by the drive roller 46 to travel in the film winding direction (the direction of the arrow). The encoder 48 controls a constant feed amount of the film 26 (for example, 0.1 m
m) to output a sampling signal.

Reference numeral 52 denotes a light source for projecting an image accommodated in the space 38 between the reel driving units 30 and 32.
It has a lamp 54, a reflector 56, a condenser lens 58, an appropriate filter, and the like. In FIG. 2, reference numeral 60 denotes a power supply circuit unit,
Reference numeral 62 denotes a power control circuit unit such as a motor.

Next, the line sensor driving section 64 will be described.
The line sensor driving section 64 is integrated with the projection lens 66. That is, as shown in FIGS. 3 and 4, the frame (rotating frame) 68 of the line sensor driving unit 64 is integrally formed with a cylindrical portion 70 for holding the projection lens 66.
The projection lens 66 held by the cylindrical portion 70 has a fixed focal point and a magnification of about twice. The cylindrical portion 70 is rotatably held by a frame (fixed frame) 72 fixed to the housing 28 so that the inclination of the image to be read can be corrected. Here, the cylinder 70 rotates about an optical axis 74 perpendicular to the film 26.

The cylindrical portion 70 of the rotating frame 68 and the pulley 76 of the servomotor 76 attached to the fixed frame 72
A belt 78 is wound around A. The rotation frame 68 is rotatable around the optical axis 74 by the rotation of the motor 76.

As shown in FIG. 4, a movable base 80 is attached to the rotating frame 68 on a surface opposite to the cylindrical portion 70. That is, the movable base 80 is provided with a pair of guide rods 82, 82.
Slidably held by the optical axis 74 near the opening of the cylindrical portion 70.
Can be reciprocated in a direction orthogonal to.

A belt 86 wound around pulleys 84, 84 is provided on the rotating frame 68 in parallel with the reciprocating direction of the movable table 80.
And one side of the movable table 80 is fixed to the belt 86. One pulley 84 has a servo motor 8
The rotation of 8 is transmitted via the belt 90. As a result, by rotating the servo motor 88 forward and backward, the movable table 8 is rotated.
0 can be reciprocated on a plane orthogonal to the optical axis 74.

The movable table 80 has guide rods 82, 82
A long window 92 is formed in a direction perpendicular to the direction of the movable table 80, that is, in a direction perpendicular to the reciprocating direction of the movable table 80. This long window 92
Is located on the optical axis 74 in the longitudinal direction. A printed wiring board 94 is fixed to the rear surface of the movable base 80, that is, the surface opposite to the cylindrical portion 70 so as to be orthogonal to the optical axis 74.

A CCD line sensor 96 facing the long window 92 is fixed to the substrate 94 (FIG. 3). The substrate 94 is also provided with a preamplifier for amplifying the output of the line sensor 96. CCD line sensor 9
Of course, the light receiving surface of No. 6 coincides with the image forming surface of the projection image of the projection lens 66.

Next, an apparatus for detecting frames will be described with reference to FIG. The upstream side of the image reading position of the microfilm 26, that is, the position of the optical axis 74 (the supply reel 24A side)
The film 26 is traversed in the width direction and the film 26
A pair of optical fiber holding blocks 100 and 102 facing each other with a slight gap therebetween are provided. Nine optical fibers 104 and 106 arranged in the film width direction are inserted through these blocks 100 and 102. The structure of these blocks 100 and 102 will be described later.

The optical fibers 104 and 106 are held perpendicular to the film 26, and their end faces face each other with the film 26 interposed therebetween. That is, the end faces of the nine optical fibers 104 face the end faces of the nine optical fibers 106, respectively. As a result, nine combinations in which the end faces face each other with the film 26 interposed therebetween can be obtained.

The nine optical fibers 104 held by the block 100 are bundled and guided to the vicinity of the lamp 54 of the light source 52. Therefore, light enters the nine optical fibers 104 from the lamp 54 and is guided to one surface (the surface on the block 100 side) of the film 26. The light source 52 will be described later.

Light emitted from nine optical fibers 104 opposed to each other enters the nine optical fibers 106 held by the block 102 via the film 26. 9
The optical fibers 106 are guided from the block 102 to the optical sensors 108, respectively. The density signals output from the nine optical sensors 108 are separately input to a binarization unit 110, where they are binarized in synchronization with a sampling signal output from the encoder 48.

Each of the nine binarized signals is determined by a decision unit 112.
The determination result of the presence or absence of a frame is obtained based on the output of each optical sensor 108 here. This determination unit 112
Is also supplied with a signal from the sensor selection unit 114. The sensor selection unit 114 controls the optical fiber 106 whose end face is located within the traveling locus width of the frame corresponding to the film shooting method.
And the optical sensor 108 connected thereto. The determination unit 112 selects only the determination result of the sensor 108 selected by the sensor selection unit 114 from these nine determination results, and determines the presence or absence of a frame according to a shooting method such as simplex, duo, or duplex.

The end faces of the nine optical fibers 104 and 106 are on a straight line L perpendicular to the running direction of the film 26 as shown in FIG. It is in. In this embodiment, since the optical sensor 108 detects the amount of light incident on the optical fiber 106, the end face of the optical fiber 106 is substantially
This is the same as the case where the optical sensor 108 is located at a position opposing to. Therefore, FIG. 6 illustrates that the optical sensor 108 is located at the end face position of the optical fiber 106 on the film 26 side.

These nine optical sensors 108 are positioned in the film width direction such that a plurality of optical sensors 108 always pass through one frame even when the film photographing method is different. FIG. 6A shows the case of the simplex system, in which case the determination unit 112 determines whether the sensor selection unit 1
The frame is detected by the eight optical sensors 108 (A) based on the output of No. 14 and the blip 1 is detected by the other optical sensor 108B.
18 is detected. Therefore, the determination unit 112 determines the presence or absence of a frame using the binarized signals output from the eight binarization units 110. For example, if a majority or a certain percentage or more of the determination results is black, it is determined that a frame exists. The determination may be made using a logical product or a logical sum of the determination results. In this case, it is also possible to search using the output of the optical sensor 108B that detects the blip 118.

FIG. 6B shows a case of the duplex system, in which the front and back of a document are simultaneously photographed on the upper and lower channels, and there is an optical sensor 108C which does not detect a frame between both channels. Therefore, in this case, the determination unit 11
2 detects the frame of each channel based on the output of the sensor selection unit 114, using the output of each of the three optical sensors 108D and 108E passing within the width of the upper and lower channels except for the output of the optical sensor 108C. I do.

FIG. 6C shows the case of the duo system.
The center optical sensor 108F does not detect a frame. For this reason, based on the output of the sensor selection unit 114, the determination unit 112 detects the frame of each channel by four optical sensors 108G and 108H included in the two groups divided into the upper and lower groups. The search unit 116 searches for a target frame by integrating the determination signals output from the determination unit 112.

Next, optical fiber holding blocks 100 and 102 for holding the ends of the optical fibers 104 and 106 are shown in FIGS.
Explanation will be made using 0. 7A and 7B are a side view and a bottom view showing a combined state of these blocks 100 and 102, FIG. 8 is an exploded perspective view of both blocks, and FIG. 9 is a sectional view of the disassembled state of both blocks. 10 is an enlarged cross-sectional view of the block showing the vicinity of the holding portion at one end of the optical fiber.

Blocks 100 and 102 having exactly the same structure are used in combination by inverting each other. That is, the two blocks 100 and 102 have their opposing surfaces made of metal plates 100A and 102A such as stainless steel, and after these metal plates 100A and 102A, 30% by weight of glass fiber is added to polybutylene terephthalate (PBT) or the like. Synthetic resins 100B and 102B mixed to a certain degree are integrally molded. Both ends of the metal plates 100A and 102A and the resins 100B and 102B are extended to form attachment portions 100C and 102C to a frame (not shown) of the device. Here, the mounting portions 100C and 102C are the blocks 10
0 and 102 are displaced in the width direction. Therefore, when the blocks 100 and 102 are combined and mounted on the apparatus frame (see FIG. 7B), it is possible to prevent a tool such as a driver from interfering with the other mounting portion 100C or 102C.

At the center in the longitudinal direction of the two blocks 100 and 102, the nine optical fibers 104 and 106 are straight lines L.
It is held at a predetermined interval above (see FIGS. 6A and 7B). Here, the optical fibers 104 and 106 are covered with a resin 202 as shown in FIG. The optical fibers 104 and 106 are exposed by peeling off the resin 202 at one end by a predetermined length, pass through the holding holes 204 formed in the blocks 100 and 102, and are fixed to the blocks 100 and 102 by the adhesive 206. And the light guide section 20
At 0, the end surface is polished together with the surfaces of the blocks 100 and 102 to make a flat surface.

Here, the metal plates 100A and 102A are shown in FIG.
As shown at 0, both edges of the opposing surfaces of the blocks 100 and 102 are smoothly polished in an arc shape. Metal plate 1
Near the center of 00A and 102A, optical fibers 104,
Oval openings 100D, 102D surrounding the end face of the opening 106 are formed (FIGS. 8, 9, 10).
Resins 100B and 102B are filled in 2D. Therefore, the surfaces of the metal plates 100A and 102A are polished so that the metal plates 100A and 102A and the openings 100D and 1A are polished.
The resin in 02D and the end faces of the optical fibers 104 and 106 are positioned on the same plane, and these can be made a smooth plane.

One of these blocks 100 and 102
At 02, a positioning reference pin 208 and a coupling pin 210 are fixed at positions as far apart as possible in the longitudinal direction. These pins 208 and 210 are pipe-shaped, are internally threaded at both ends, and have a flange 212 at the center. The reference pin 208 is inserted from the metal plate 102A side into a circular hole (reference hole) 214 formed in the metal plate 102A and the resin 102B of the block 102, and the screw 216 is screwed into the block 102 from the resin 102B side. Fixed.

Similarly, the connecting pin 210 is connected to the metal plate 102A.
In addition, screws 220 are temporarily fixed to long holes 218 long in the longitudinal direction of the block 102 formed in the resin 102B. On the other hand, the other block 100 has a circular reference hole 222 into which the reference pin 208 is non-movably fitted, and an elongated hole 224 long in the longitudinal direction of the block 100 into which the coupling pin 210 is movably engaged. .

Therefore, when assembling these blocks 100 and 102, first, the reference holes 22
2 is fitted to the reference pin 208 of the block 102,
At the same time, the blocks 100 and 102 are combined while the slot 224 is engaged with the coupling pin 210. Then, screws 226 and 228 are inserted from the block 100 side into the pin 208
The screw 220 of the connecting pin 210 may be screwed from the block 102 side.

At this time, the flanges 212 provided on the pins 208, 210 keep the gap between the blocks 100, 102 constant, and electrically connect the metal plates 100A, 102A to keep them at the same potential. These metal plates 1
00A and 102 are grounded by connecting the mounting portions 100C and 102C to the device frame.

As described above, both blocks 1 are
Since the positioning in the width direction is performed by the connecting pin 210 while the positioning in the longitudinal direction of 00 and 102 is performed, both blocks 1
The optical axes of the optical fibers 104 and 106 of 00 and 102 can be aligned and held with high precision. Pin 208,
By unscrewing the screws 216, 220 or 226, 228 of the 210, the two blocks 100, 102 can be easily disassembled, and the end faces of the optical fibers 104, 106 can be cleaned to remove dirt.

The reference holes 2 in both blocks 100 and 102
The processing of 14, 222 and the long holes 218, 224 for coupling can be performed as follows. One method is to set both blocks 100 and 102 in a separately prepared jig, fix the optical fibers 104 and 106 with their optical axes aligned, and then drill by passing through both blocks 100 and 102. The reference holes 214 and 222 or the coupling long holes 218 and 224 may be simultaneously processed. Another way is
The resin 100B and 102B sides of the blocks 100 and 102 are integrally formed by one common mold, and the reference holes 2 are formed.
After the holes 14, 218 and the connecting long holes 218, 224 are simultaneously drilled, the resin portion is divided by a cutter. Further, the metal plates 100A, 102
A may be formed in a cylindrical shape and a resin is filled therein.

Next, based on FIG.
A light source for guiding light to the light source will be described. In the present invention, the optical fiber 10
As a light source for guiding light to the light source 4, the light source unit for image projection is also used. That is, the light source of the optical fiber 104 includes a lamp 54 of the light source unit for image projection, a light shielding plate 56A that blocks direct light incident on the optical fiber 104 from the lamp 54,
The light reflected by the lamp 54 is formed by a reflector 56 for guiding the optical fiber 104.

In this embodiment, the reflector 56 of the lamp 54 is formed in a box shape as shown in FIG.
A small hole 56B is formed in one wall surface. The ends of the nine optical fibers 104 are converged, and the end surface of the converging portion 104A is held so as to face the inside of the box-shaped reflecting plate 56 from outside the small hole 56B. Further, the light shielding plate 56A prevents the light of the lamp 54 from directly entering the small hole 56B in this box.

For this reason, a part of the light of the lamp 54 passes through the condenser lens 58 as described above and passes through the film 26.
And a part of the light from the lamp 54 is reflected by a box-shaped reflector 56, passes through the small hole 56B, and enters the optical fiber 104. Since the light entering the optical fiber 104 is reflected light by the reflection plate 56, the optical path length from the end face of the optical fiber 104 to the lamp 54 becomes long, and the lamp 54 is substantially far from the end face of the optical sensor 104. Become. Therefore, the light of the lamp 54 is reflected by the reflection plate 5.
The light enters the optical fiber 104 in a complicated and repeated manner within the optical fiber 104. As a result, the light incident on the optical fiber 104 is equalized and becomes closer to parallel light.

The nine optical fibers 104 held in the block 100 have the same length, and the nine optical fibers 106 held in the block 102 have the same length. For this reason, the conditions of each pair of the nine optical fibers 104 and 106 are made uniform, and the accuracy of frame detection is improved.
Further, since the reflecting plate 56 is formed in a box shape, the lamp 54
Light is reflected repeatedly in this box in an intricate manner,
Accordingly, the effect of the present invention is further enhanced.

In this embodiment, the optical fiber 1
04, 106, the narrow film 26
The end faces of these optical fibers 104 and 106 can be arranged close to each other in the width direction. However, the present invention also includes the case where one optical fiber is held in each of the blocks 100 and 102. In this case, the binarizing unit 110
Is directly used as a determination signal indicating the presence or absence of a frame, so that the determination unit 112 is unnecessary.

In this embodiment, since the density sensors (optical sensors) are arranged on the straight line L perpendicular to the film running direction, the presence or absence of a frame can be detected at the same time. Therefore, unlike the case where a plurality of density sensors (optical sensors) are arranged shifted in the running direction of the film, it is not necessary to correct the output timing of each density sensor (optical sensor), and the circuit configuration is simplified. .

[0051]

As described above, according to the first aspect of the present invention, the light source for guiding the light to the optical fiber includes the lamp of the light source for image projection and the light shielding for blocking the direct light directly entering the optical fiber from the lamp. Since it is formed by the plate and the reflector for guiding the reflected light of the lamp to the optical fiber, the intensity distribution of the light incident on the optical fiber is homogenized. For this reason, a dedicated lamp or a diffusion plate for guiding light to the optical fiber is not required, so that the apparatus can be downsized and the number of parts is reduced.

Here, when a plurality of optical fibers are held in each block, and a frame is detected at different positions in the width direction of the film, the ends of the optical fibers on the light source side are converged to face the lamp side. (Claim 2). In this case, light close to the same condition can be made incident on the plurality of optical fibers, and the conditions under which a plurality of pairs of optical fibers facing each other across the film detect a coma can be made uniform.

If the lengths of the plurality of optical fibers held in each block are made equal, the amount of light attenuation in each optical fiber can be made uniform, and the detection condition of the frame can be made uniform. 3). The reflector that reflects the light of the lamp and guides the light to the optical fiber is formed in a box shape, and the optical fiber is made to face the inside of the box-like reflector through a small hole formed in one wall surface of the box-like reflector. Can be held (claim 4). In this case, the effect of the present invention is further enhanced because the light of the lamp is incident on the optical fiber after being repeatedly reflected in a complicated manner in the box-shaped reflector.

[Brief description of the drawings]

FIG. 1 is a diagram showing a use state of an embodiment of the present invention.

FIG. 2 is a perspective view showing the inside of a scanner used here in a see-through manner;

FIG. 3 is a side view showing the arrangement of the main part.

FIG. 4 is a perspective view showing a line sensor driving unit.

FIG. 5 is a diagram showing a main part.

FIG. 6 is a diagram illustrating an arrangement of optical sensors.

FIG. 7 is a side view and a bottom view showing a combined state of both blocks.

FIG. 8 is an exploded perspective view of both blocks.

FIG. 9 is an exploded sectional view of both blocks.

FIG. 10 is an enlarged sectional view of a block showing the vicinity of a holding portion of the optical fiber.

FIG. 11 is a sectional view showing an embodiment of a light source unit.

[Explanation of symbols]

 26 Microfilm 52 Image projection light source 54 Lamp 56 Reflector 56A Light shield 56B Small hole 100, 102 Optical fiber holding block 104, 106 Optical fiber 104A Focusing unit 108 Optical sensor 110 Binarization unit 112 Judgment unit 114 Sensor selection unit 116 Search Unit

Claims (4)

[Claims] 1. A microfilm search apparatus for determining the presence or absence of a frame from a density change in a running direction of a microfilm, comprising: a pair of optical fiber holding blocks that cross the microfilm in a width direction and face both sides of the microfilm. An optical fiber whose one end face is penetrated and held in both blocks, facing each other across a microfilm, a light source for guiding light to the optical fiber held in one block, and a light held in the other block. An optical sensor that detects the amount of light incident on the fiber, a binarizing unit that binarizes the output of the optical sensor, and a searching unit that determines the presence or absence of a frame based on the binarized signal and searches for the frame. Comprising, the light source is a lamp of a microfilm image projection light source,
A micro-filter comprising: a light-shielding plate that blocks direct light from the lamp to a light-source-side end face of the optical fiber on the light source side; and a reflector that guides reflected light of the lamp to the optical fiber. Film search device. 2. A pair of optical fiber holding blocks hold one end of each of a plurality of pairs of optical fibers opposed to each other across a film at different positions in the film width direction, and the light source side ends of the optical fibers are converged. 2. The microfilm search device according to claim 1, wherein the microfilm search device faces the lamp. 3. The microfilm search device according to claim 2, wherein the plurality of optical fibers held by the same optical fiber holding block are set to the same length. 4. The reflector is formed in a substantially box shape surrounding the lamp,
4. The microfilm search apparatus according to claim 1, wherein the end face of the optical fiber is held so as to face the inside of the box-shaped reflector from a small hole formed in one wall surface of the box-shaped reflector.