JPS59160271A - Mark detecting device - Google Patents

Abstract

PURPOSE:To make it unnecessary to execute an adjustment whenever a detecting device is replaced by constituting a photoelectric transducer and its output potential adjusting means so as to be freely attachable and detachable. CONSTITUTION:A mark detector 11 is adhered to a prescribed position, and the light of a constant light quantity is irradiated to each photoelectric transducer 251-253 of this mark detector. Subsequently, when a retrieval number of a desired information is inputted and a retrieval start is instructed, a film is shifted to detect a mark on the film successively by the transducers 251-253. When the transducers 251, 252 detect the mark simultaneously, an AND GATE AG43 is opened, and subsequently, when the transducers 252, 253 detect the mark simultaneously, an AG44 is opened. Accordingly, when the transducers 251-253 detect the mark simultaneously, an AG46 is opened, and in this case, a signal outputted from the AG46 is sent as a mark counting signal to a counter and counted.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mark detection device for detecting marks on an image support.

Conventionally, films used in search devices built into microfilm readers and the like have been provided with counting marks on the side edges of each frame of the film. The above-mentioned search device automatically searches for frames by illuminating the marks on the film with a lamp.
When the film is moved, the light flux from the mark is detected by a mark detector with a photoelectric conversion element, the output signal of the photoelectric conversion element is counted by a counter (1), and the count contents of this counter are input from the keyboard. The comparison circuit compares the desired frame number with the desired frame number, and when the two match, the comparison circuit issues a stop signal to the drive control circuit, stopping the drive system that transports the film, and setting the desired frame number to be projected on the screen. It is designed to remain stationary in position. Mark detectors usually detect dust on the film,
In order to prevent erroneous signals from being generated due to scratches or to define the stop position of the frame, it has multiple photoelectric conversion elements, and the multiple photoelectric conversion elements are spaced apart at intervals slightly shorter than the length of the mark. They are arranged side by side in the direction of film movement.

A search device configured in this way will not have any problems as long as the shape of the mark on the film is constant, but since the shape of the mark is not standardized, the shape of the mark on commonly used films varies in length. Therefore, only films with marks of a certain length are used in one retrieval device, and only films with marks of different lengths are used. If the position deviates from the predetermined position, the search cannot be performed correctly. Therefore, we prepared multiple mark detection devices corresponding to the type of mark, made them replaceable, and changed the position or number of photoelectric conversion elements arranged in each mark detection device depending on the length of the mark. A known method is to select a mark detection device corresponding to the mark on the film to be used, and to perform a search operation by attaching the selected mark detection device to a predetermined position of a search device.

However, with this method, due to variations in the performance of the photoelectric conversion element, errors in placement position, etc., even if the photoelectric conversion element receives a constant amount of light, its output potential varies, resulting in incorrect search operations. It is necessary to adjust the potential of the signal sent to the search device each time the mark detection device is replaced to prevent this from occurring, which is extremely troublesome.

An object of the present invention is to provide a mark detection device that (3) can always perform a correct search operation in a stable condition without having to make adjustments every time the mark detection device is replaced.

The details of the present invention will be described below with reference to the drawings.

FIG. 1 shows a microfilm reader equipped with a retrieval device to which the present invention is applied.

In the figure, 1 is a film supply reel, 2.3 is a film guide roller, 4 is a lamp that illuminates the microfilm, 5 is a condensing lens, and 6.7d is a glass plate 4 placed oppositely across the film transport path. 8 is the capstan roller,
9 is a pinch roller, and 10 is a film take-up reel.

The supply reel 1 and take-up reel 10 are connected to a film tensioning and winding motor, and the capstan roller 8 is connected to a film drive motor.

The microfilm P is stretched between the supply reel 1 and the take-up reel 10, and is wound onto the take-up reel or rewound onto the supply reel by driving the capstan roller 8.

11 is a mark detector, 12 is a projection lens, and 13 is a screen. As shown in FIG. 4, the microfilm F has frames 15 on which images are recorded, marks 16 attached to the side edges of each frame and having different densities from the periphery, and a glass plate 6. When the frame passes between the frames 7 and 7, it is illuminated by the light from the lamp 4, and an image of the illuminated frame is projected onto the screen 13.

As shown in FIG. 2, the mark detector 11 includes a movable substrate 21 having an opening 20 and photoelectric conversion elements 251, 252, 2.
51 and volumes 271, 272, 27. Each photoelectric conversion element is held at the side edge of the opening 20 by a block 2611C. As shown in FIG. 3, an i-screen 28 having three apertures 281, 282, and 28 degrees is provided on the front surface of the block 26 facing the film transport path, and each photoelectric conversion element 251 is attached to each aperture of this mask.
, 252.25+1 light receiving surfaces are arranged opposite to each other.

The three photoelectric conversion elements 251, 252, and 25s are arranged side by side in the film transport direction, and the photoelectric conversion elements 251 and 2
They are arranged at equal intervals so that the length l between the light receiving surfaces of the film F is slightly shorter than the length of the mark 16 or the image of the mark on the film F used.

Furthermore, each photoelectric conversion element has an electric wire of 291°292.
29. are connected to volumes 271 and 272.27g fixed to the board 21 and provided at 3 degrees from the front stand. The volumes 271, 272, and 27s are not variable resistors, but are used to adjust the output voltage of the photoelectric conversion element. The output terminal of each volume is connected to an electrical terminal group 31 provided at the tip of the stand 30. 357,556,5
5. are code signal generation terminals, and terminals 358 and 55. are electrically connected.

A connector 53 having terminals that electrically connects with each terminal of the mark detector 11 when the mark detector 11 is mounted at a predetermined position on the support base 32 on the main body side is disposed on the search device main body side. .

This connector has terminals at positions corresponding to the respective terminals of the mark detector 11, and these terminals of the connector are connected to a control circuit of a search device to be described later. When the mark detector is attached to a predetermined position (6) and the film is transferred, the light beam of the lamp 4 that enters the photoelectric conversion element is blocked by the mark, so that the amount of light that enters the element changes, and each photoelectric conversion element changes. Element 25
．． ．． 252.25. A pulse signal is generated from the

FIG. 5 shows the control circuit of the search device, and shows the mark detector 11.
The terminals of the mark detector 11 are electrically connected to the terminals of the connector 33 at a position of the break FJ a.

In Fig. 5, 41), 41.42 are amplifier circuits, and the photoelectric conversion elements 251, 252, 253 are connected to them.
When it detects a mark, that is, when the light incident on the light-receiving surface of the photoelectric conversion element is blocked by the mark, it outputs a high-level signal. 43 to 46 are AND gates, 47 is an OR gate, and 48 is an inverter.

When the mark detector 511 is attached to a predetermined position of the search device, the terminals 3s, . . . , 3sp of the mark detector 11 are grounded, and the terminal 357 is connected to the power supply V.

(7) Other mark detectors have similar terminals 357-359,
The connection status of these terminals differs for each mark detector, and when the mark detector is attached to the search device, the type of mark detector is determined based on the connection status of these terminals 357 to 359, The search device is switched to perform the correct search operation using the attached mark detector.

In this embodiment, when the mark detector 11 is attached, a high level signal is input to the input terminal 441 of the AND gate 44, and a low level signal is input to the input terminal 451 of the AND gate 45.

Next, the operation of the above device will be explained. Now, it is assumed that the mark detector 11 is attached to the search device and a search is performed. First, the mark detector 11 is mounted at a predetermined position 1#, and a constant light J# is applied to each photoelectric conversion element 251 to 253 of this mark detector.
irradiate with light.

When the output terminals of each volume 271 to 273 output signals of the same level,
273, thereby photoelectric conversion elements 251 to 25
Correct the variations in sensitivity etc. in step 3 and (8) ensure that the mark can be detected.

Next, when the user inputs a search number for desired information and instructs to start a search, the capstan roller 8 rotates and the film y is transported in the direction in which it is wound onto the take-up reel 10. As the film is transferred, the mark 16 on the film becomes a photoelectric conversion element 25.
1 to 253 are sequentially detected, and the photoelectric conversion elements 25. ．．
When the photoelectric conversion elements 252 and 25s simultaneously detect the mark 16, the AND gate 43 opens, and when the photoelectric conversion elements 252 and 25s simultaneously detect the mark 16, the AND gate 44 opens. Therefore, the photoelectric conversion elements 251 to 25. When the marks are detected at the same time, the AND gate 46 opens, and the signal outputted from the AND gate 46 at this time is sent to the counter as a mark count signal and counted. Since the details of the search device are publicly known, their explanation will be omitted. When the desired information mark is detected, the film stops, and when the film stops, the state shown in FIG. 4 is reached.

The tJz diagram shows another mark detector, and this mark detector 111 is installed in the retrieval device when using the microfil (9) 5F' shown in FIG.

The mark detector 111 is the mark detector 1 shown in FIG.
1, and similar parts are designated by the same reference numerals. As shown in FIG. 6, the mark detector 111 includes three photoelectric conversion elements 1251, 1252, 125.
These photoelectric conversion elements are arranged in the same manner as the photoelectric conversion elements 251 to 25° of the mark detector 11. The mark 16' has a shorter length in the film transport direction than the mark 16 in FIG. 4 so that the photoelectric conversion elements 1251 to 125S cannot detect the mark 16' at the same time. Each photoelectric conversion element 1251-125. are connected to volumes 1271-1275 by electric wires 291-295. Also, the terminals 357 to 35 of the mark detector 111? Terminal 3
57 and 359 are electrically connected.

When the mark detector 111 is attached to a predetermined position of the search device and the light of a constant scene similar to that described above is irradiated to each photoelectric conversion element 1251 to 125s, each volume 1271 to 1
Adjust each volume so that the signal at the same level as above is output from the output terminal of 273 (set to 1).Differences in the sensitivity of the photoelectric conversion elements of each mark detector and differences in the placement positions of the photoelectric conversion elements It is possible to correct variations in the output potential of each photoelectric conversion element due to

Therefore, if the volume of each mark detector is adjusted in advance, there is no need to adjust the retrieval device each time a mark detector is replaced, as is the case in the past, and the retrieval work becomes extremely simple.

When the mark detector 111 is attached to a predetermined position and a search operation is performed using the film 1, the optical IRS conversion element 12
The relative positional relationship between 51 to 125s and mark 16' is 6th.
When the state shown in the figure is reached, that is, the photoelectric conversion element 1251
．． 1252 detects the mark 16' at the same time, and when the remaining photoelectric conversion element 1253 does not detect the same mark 16', the AND gate 46 shown in FIG. 5 opens and outputs a mark count signal.

In the above embodiment, the light from the mark is directly detected by the photoelectric conversion element, but the light from the mark may be guided to the photoelectric conversion element through an optical member such as an optical fiber bundle.

θ1) In addition, the output potential of the photoelectric conversion element is adjusted by a volume, but a light amount adjustment member such as an aperture or a filter is provided in front of the photoelectric conversion element, and this light i' adjustment member allows the light to be transferred to the photoelectric conversion element. It is also possible to adjust the output potential of the photoelectric conversion element by controlling the amount of incident light. The mark detector only needs to be equipped with at least one photoelectric conversion element and a means for adjusting the output potential of this element. Each detector is configured so that the arrangement of the conversion elements, the number of photoelectric conversion elements, etc. are different, and a mark detector corresponding to the shape of the mark is selected and attached to the search device.

Note that the output of the code signal generation terminal of the mark detector is used to switch the search device to perform the appropriate search operation, but even if the switch is manually switched when the mark detector is attached, good.

As described above, according to the present invention, there is no need to adjust the voltage θ2) of the signal input to the search device each time the mark detection device is replaced, and the search operation is extremely simple and prevents erroneous search operations. There will be no fear of it happening.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram of a film reader to which the present invention is applied, Fig. 2 is a perspective view of a mark detector, Fig. 3 is a sectional view of the mark detector, and Fig. 4 is a relative view of the photoelectric conversion element and the mark. Figure 5 is a diagram explaining the positional relationship; Figure 5 is a diagram illustrating the main part of the control circuit of a search device equipped with a mark detector; Figure 6 is a diagram explaining the relative positional relationship between marks on other films and photoelectric conversion elements. , FIG. 7 is a perspective view of another mark detector. 11...i-ri detector 251, 252, 25. ...Photoelectric conversion element 271.2
72,273・Fist・Volume Applicant Canon Co., Ltd. θ3)

Claims (1)

[Claims] A mark detection device characterized in that a photoelectric conversion element for detecting an optical signal from a mark and a means for adjusting an output potential of the photoelectric conversion element are arranged on a substrate, and the substrate is configured to be detachably attached to a search device.