JPH0619506B2 - Information retrieval device - Google Patents

Description

The present invention relates to an information retrieving apparatus for retrieving desired information in a recording medium by detecting a mark on an information recording medium such as a film having a mark whose density is different from that of the periphery.

〔Purpose〕

In a film reader or reader printer equipped with a search device that uses a film on which a large number of information and search marks are recorded, the film is illuminated by a lamp, and the frame information of the illuminated film is projected onto a screen or photoconductor by a projection lens. I am trying to project.

In this type of apparatus, optical components such as an imaging lens are configured so that the illuminance distribution on the screen or the photoconductor is uniform.

On the other hand, in the search device, the optical mark on the film during movement of the film is detected by the mark detector made of a photoelectric conversion element, and the pulse signal output when the mark detector detects the mark is counted by the counting unit, When the count value of the counting unit and the frame number of the desired information match, the film is stopped and the information of the desired frame is projected on the screen or the photoconductor. Generally, the mark detector is arranged in the vicinity of the film feeding path and detects the light transmitted through the base portion and the mark portion of the film when the film is moved.

By the way, the illuminance distribution on the film surface decreases as it moves away from the optical axis as shown in FIG. 1, and as a result, the illuminance distribution on the film surface becomes uneven. In order to adjust the position of the image on the projection surface, the film and the mark detector are integrally displaced in the film width direction, or the mark detector is displaced in the film width direction according to the position of the mark on the film. Then, the amount of light incident on the mark detector largely changes, and as a result, the mark detector cannot detect the mark accurately, and there is a problem of retrieving incorrect information.

The present invention is intended to solve the above problems, and is to change the illuminance distribution on the surface of a recording medium during search and during non-search.

〔Constitution〕

 The present invention will be described below with reference to specific examples shown in the drawings.

2 and 3 show a film reader printer provided with an information retrieval device to which the present invention is applied, FIG. 2 is a schematic configuration diagram, and FIG. 3 is a perspective view of a film feeding mechanism.

In FIG. 2, 1 is a lamp for illuminating the microfilm F, 2 and 3 are condenser lenses, 4 is a mirror for changing the optical path by 90 °, 5 is a light shielding plate for changing the illuminance distribution,
An image forming lens 6 projects the frame information of the film illuminated by the light of the lamp 1 onto the screen 7 or the photosensitive drum 8. Reference numeral 9 denotes a mirror for switching the optical path, which moves to a solid line position and a broken line position, moves to a solid line position when observing information on the screen, and moves to a broken line position when copying.

In FIG. 3, 11 is a film supply cartridge for storing the microfilm F in a roll shape, 12 is a capstan roller for sending out the microfilm in the cartridge, M1 is a motor for driving the capstan roller 12, and M2 is A film rewinding motor for rewinding the film onto the film reel in the cartridge, SOL1 is a solenoid for bringing the capstan roller 12 into contact with the microfilm F via the support arm 13, and 14 is a support arm 13.
A spring SOL2 is a brake solenoid for the film rewinding motor M2, which moves the plunger 13a / capstan roller 12 to separate the capstan roller 12 from the microfilm.
When 2 does not operate, the film rewinding motor M2 is rotatable, and when the brake solenoid SOL2 operates, the brake plate 15 fixed to the motor shaft is attracted to prevent the film rewinding motor M2 from rotating.

16 and 17 are film guide rollers, 18 is a take-up reel, M3 is a film take-up motor for driving the take-up reel 18, and SOL3 'is a brake solenoid for the motor M3.

Although not shown, a guide plate for guiding the film is provided along the film feeding path between the cartridge 11 and the take-up reel 18.

Reference numeral 20 denotes a known mark detector provided on the side of each frame of the microfilm F to detect the search mark m having a density different from that of the periphery.

The mark detector 20 has a photoelectric conversion element and is arranged in the vicinity of the film feed path. When the film F is fed, the light from the lamp 1 is interrupted by the mark m to detect the mark. A signal is emitted, and this mark detection signal is counted by the counter of the search device. Since the details of the search device are publicly known, description thereof will be omitted.

When a frame number of a desired frame is input to the input circuit of the search device, the motor M1 rotates and the solenoid SO
When L1 is activated, the capstan roller 12 comes into contact with the microfilm F coming out of the cartridge 11 and the microfilm F is pulled out from the cartridge 11 and the tip thereof is fed toward the take-up reel 18. When the tip of the microfilm approaches the take-up reel 18, the take-up motor M3 rotates and the tip of the microfilm winds around the take-up reel 18, and when the autoloading ends, the motor M1 and the solenoid SOL1 become inoperative. , The microfilm F is continuously fed by the rotation of the take-up reel 18.

During feeding of the microfilm, the number of marks m detected by the mark detector 20 is counted by the counter and compared with the numerical value of the frame number input in advance. When the numbers match, a stop signal is generated from the counter to generate the brake solenoid SOL3. Operates to brake the winding shaft 21, and the SOL2 also brakes the shaft of the motor M2.
As a result, the inertial rotation of the film reel in the cartridge 11 is stopped, the feeding of the film is stopped, and the frame image of the designated number is projected on the screen 7 or the photosensitive drum 8 via the imaging lens 6.

4 and 5 show a mechanism for changing the illuminance distribution. The light shielding plate 5 arranged in the illumination section of the reader / printer is fixed to the arm 25, and the arm 25 is connected to the rotary solenoid 26. However, the rotary solenoid 26 moves it in and out of the illumination optical path. The rotary solenoid 26 is turned on / off according to the search operation of the search device. When the rotary solenoid 26 is on, the arm 25 is moved to the broken line position to place the light shielding plate 5 outside the illumination optical path, and when it is off, the arm 25 is moved.
Is moved to the solid line position and the light shielding plate 5 is placed near the optical axis of the illumination optical path. The illumination range on the film is constant regardless of the position of the light shielding plate 5.

When the light shielding plate 5 is placed outside the illumination optical path, the illuminance distribution on the film surface is not uniform as shown in FIG. 1, but the illuminance distribution on the screen or the photosensitive drum surface is almost uniform. The imaging lens 6 is designed for the. In addition,
A slit is arranged between the imaging lens 6 and the photosensitive drum 8, and the slit makes the illuminance distribution on the photosensitive drum surface more uniform.

The rotary solenoid 26 receives a control signal from the search device and is turned on when the search operation is started, that is, when the film feeding motor M2 or M3 is driven, and the light shielding plate 5 is arranged at a predetermined position in the illumination optical path. The light shielding plate 5 has a circular shape that blocks only a part of the light in the illumination light path, and when placed at a predetermined position in the illumination light path, blocks the light passing near the optical axis of the illumination light path as shown in FIG. Then, the amount of light near the optical axis of the illumination optical path is reduced, and the illuminance distribution on the film surface is made substantially uniform. Therefore, in order to adjust the position of the image projected on the screen in the reader state, the carrier holding the film and the mark detector (not shown) is displaced in the film width direction and the position of the mark on the film is adjusted. Even if the mark detector is displaced in the film width direction to match the detection position of the mark detector with the detection position of the mark detector, regardless of the position of the mark detector, the luminous flux incident on the mark detector during search is almost constant, and as a result False search can be prevented.

FIG. 6 shows the illuminance distribution on the film surface when the shading plate 5 is arranged at a predetermined position in the illumination optical path. When the shading plate 5 is inserted in the illumination optical path, the illuminance distribution on the film surface becomes substantially uniform. Therefore, even if the position of the mark detector is displaced in the film width direction, the amount of light incident on the mark detector hardly changes, so that the mark can be accurately detected.

As a means for changing the illuminance distribution on the surface of the recording medium, a density filter or a liquid crystal plate capable of changing the light transmission distribution can be used. The illuminance distribution may be changed by relatively changing the positions of the lamp and the condenser lens.

〔effect〕

As described above, according to the present invention, while controlling the illumination range to be constant, the amount of illumination light near the optical axis is reduced during search as compared with non-search, so that a desired image can be observed on the screen or printed. During non-search, the desired image can be illuminated with high illuminance, so a high-quality projected image can be obtained.On the other hand, during search, the amount of illumination light near the optical axis decreases, so the illumination range remains constant on the film. Illuminance distribution can be made substantially uniform, and even if the position of the recording medium is changed within this range, the amount of illumination light does not fluctuate, the mark can be reliably detected, and erroneous search can be prevented. .

[Brief description of drawings]

1 is a diagram showing the illuminance distribution on the film surface, FIG. 2 is a configuration diagram of a reader printer to which the present invention is applied, FIG. 3 is a perspective view of a film feeding mechanism, and FIG. 4 is a configuration diagram of an illuminating section. FIG. 5 is a diagram showing the relationship between the condenser lens and the light shielding plate, and FIG. 6 is a diagram showing the illuminance distribution on the film surface at the time of retrieval. 1 ... Lamp, 2.3 ... Condenser lens 5 ... Shading plate, 6 ... Imaging lens

Claims (1)

[Claims] 1. A transport means for transporting an information recording medium having a mark formed on a side of image information, an illuminating means for illuminating the image information and the mark on the information recording medium, and an information recording illuminated by the illuminating means. A detection means for optically detecting a mark on the medium; an optical system for projecting image information of the information recording medium illuminated by the illumination means; and a control means for changing the illumination light amount distribution of the illumination area by the illumination means. The control means controls so that when the desired image information is searched by detecting the mark by the detection means, the illumination range is kept constant, and the illumination light amount near the optical axis is reduced as compared with the non-retrieval time. An information retrieval device characterized by the above.