JPH08234332A - Image pickup device - Google Patents

Abstract

PURPOSE: To prevent the erroneous operation of a sensor for detecting a subject, and enhance the reliability of image pickup by providing a means for removing a prescribed high frequency component of the output signal of the sensor between the output of the sensor and the input of a light emitting device. CONSTITUTION: When the carrying speed of a form 37 is set, for example, to about 1m/sec, and the falling directional length of the subject 37, for example, to about 10cm, the subject passing time of the sensing area of a paper sensor 38, or the output of the paper sensor 38 shows 'presence of paper' for about 0.1 second. On the other hand, when the light emitting time of a stroboscope 21 having a short light emitting time is about 0.001 second, the detecting time is 0.001 second even when the stroboscopic light is incident on the paper sensor 38, and the cut-off frequency of a low pass filter 46 is thus set to about 40-200Hz, thereby, the erroneous detection of the paper sensor 38 resulted from the stroboscopic emission can be eliminated. The stroboscopic emission is caused only when the subject 37 is present in the image pickup area regularly synchronously with the paper feed, and a CCD camera 22 performing an image pickup operation synchronously with the stroboscopic emission can take a normal image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for illuminating and picking up an image of an object which is conveyed and supplied.

[0002]

2. Description of the Related Art Conventionally, in a still image recording (printing) device such as a facsimile or a scanner, a CCD (electronic image pickup camera) is used.
Since the original is read using the line sensor, the paper that is the subject is always constrained, and the paper feed speed is very slow (about 10 cm / sec). The imaging method is that the paper is detected by the paper sensor (position detection) while the paper is fed to the imaging position at a slow speed, the object is divided into a plurality of lines, and a light bulb and a fluorescent lamp are provided for each line of the object. Is irradiated with continuous weak light and recorded separately by a CCD (electronic imaging camera). The paper sensor is usually of an optical type, and is composed of a light emitting section that emits weak light and a light receiving section that are located opposite each other with the paper sandwiched between them. The paper sensor detects the interruption of light by the paper and determines the presence or absence of the paper. .

In a line-sensor type image recording apparatus, by partially recording an object, the paper sensor and the irradiation apparatus for the object are separated from each other so that the irradiation light of the object does not hit the paper sensor completely. Since the shielding is easy, the recording device does not malfunction due to the paper sensor erroneously detecting, for example, "no paper (paper passing)" by the irradiation light of the subject. In addition, since the subject is always transported in a restrained state, even if the paper sensor detects "no paper" at abnormal timing, it is easy to determine whether or not the paper sensor is correct. Is.

Japanese Patent Laid-Open No. 3-37556 proposes a paper machine equipped with a paper quality measuring device. In a paper machine, the paper that is the subject is always supplied continuously at low speed, so when measuring the paper quality by irradiating strobe light, the timing of strobe emission may be at a fixed cycle, and a paper sensor that detects the presence of paper It is not necessary to control the timing of strobe emission in synchronization with.

[0005]

However, the energy of the strobe light for imaging reaches about one million times the energy of the light emitted by the photosensor used for detecting the position of the object. Therefore, when the optical sensor detects paper and emits strobe light, the optical sensor may erroneously detect strong strobe light, and the optical sensor may erroneously detect “no paper or paper passes”. Then, the false signal of the optical sensor causes the strobe to erroneously emit light, and the erroneous strobe emission causes the optical sensor to output a pseudo signal, which causes a vicious cycle (chain reaction) in which the strobe emits light.

Even if the optical sensor and the stroboscopic light emitting area are completely separated or shielded, it is difficult to prevent the stroboscopic light from entering the paper sensor because the stroboscopic light emits strong light and is reflected inside the apparatus. For example, there is a possibility that strong strobe light may leak from a paper conveyance path or the like, and in order to increase the reliability of the optical sensor by eliminating the above-mentioned separation or shielding, the number of parts is increased, the device is increased in size, and the cost is increased. To rise.

In continuous imaging, when the second paper passes the sensing position of the paper sensor, and the strobe for photographing the first paper conveyed first emits light, the paper sensor causes the strong strobe light to leak. Upon receiving the light, it is determined that the second paper has already passed the sensing position of the paper sensor (though the output light of the paper sensor is blocked by the second paper),
Even though the second paper has not reached the imaging position,
There is a possibility that a flash may be emitted to capture an aerial image.

In the page-type image recording apparatus, the subject on which an image is recorded is intermittently supplied one after another,
It is necessary to synchronize the position of the subject with the light emission timing for imaging. If the light emission timing is once misaligned, especially when the subject is transported at high speed (high speed imaging), a series of imaging errors due to insufficient light amount occurs.

Particularly, the transportation (movement) of the object to the image pickup position
When the degree of freedom of the subject is high, unlike the case where the subject is completely restrained by the subject transport device, it is required to strictly grasp the current position of the moving subject. Further, it is more difficult to completely shield or separate the sensing range of the paper sensor and the stroboscopic light emitting region in order to increase the degree of freedom in supplying and conveying the subject, increase the conveying speed, and reduce the number of parts. .

The present invention has been made in view of the above problems, and in an apparatus for photographing a subject by emitting light in accordance with the detection timing of the subject, malfunction of a sensor for detecting the subject is prevented, and image pickup is performed. An object is to provide an imaging device that enhances reliability.

[0011]

In order to achieve the above object, an image pickup device of the present invention comprises a sensor for detecting a subject,
A light emitting device that receives the output of the sensor as an input and emits light according to the output of the sensor and a means for capturing an image of a subject are provided, and a predetermined high-frequency component of the output signal of the sensor is provided between the output of the sensor and the input of the light emitting device. Is provided.

The image pickup apparatus of the present invention is preferably an optical sensor for detecting the position of an object and outputting an object position detection signal, and a strobe light emission which receives the output of the optical sensor as an input and emits light according to the output of the optical sensor. A device, a buffer for inputting a subject position detection signal output from the optical sensor, amplifying and outputting the signal, and an input of the amplified subject position detection signal output by the buffer, and a predetermined one of the amplified subject position detection signals. A filter that removes high-frequency components, a waveform shaping means that receives the output of the filter as an input, and performs waveform shaping to output a pulse signal, and a timing generation circuit that outputs a strobe emission control signal according to the output of the waveform shaping means, Strobe device that emits light based on the strobe emission control signal output from the timing generation circuit, and strobe emission control output from the timing generation circuit Characterized by comprising a camera for imaging based on the item. Further, preferably, the subject is mainly composed of a paper member, and falls between the sensors substantially vertically.

[0013]

According to the present invention having the above structure, means for cutting a predetermined high frequency component of the signal output from the sensor is provided between the output of the object position detecting sensor and the input of the light emitting device. As a result, the false signal output from the position detection sensor of the subject due to the light emission for illuminating and imaging the subject is eliminated by the simple configuration. Therefore, the timing of position detection by the position detection sensor and the timing of light emission and image pickup are always maintained normally, and the reliability of image pickup recording is improved.

In particular, in an apparatus which conveys a subject at high speed and uses a stroboscopic image, when an optical sensor is used to detect the position of the subject, it is possible to prevent erroneous detection of paper due to malfunction of the paper sensor even when strong strobe light is emitted. High-speed and highly reliable imaging is realized.

For example, after a lapse of a predetermined time from the time when the rear end of the subject passes through the sensing area of the optical subject detection sensor, it is determined that the subject is located at the center of the angle of view (shooting area) of the camera, and the light emitting device is turned on. In a device that emits light and continuously captures an image, when a subject is conveyed at high speed, the first paper is fed into the shooting area, and the second subject reaches the sensing area of the subject detection sensor. The strobe light for photographing the first paper may be emitted.

At this time, the subject detection sensor determines that the second subject has already passed the sensing area due to the strong light leakage of the strobe light, outputs a high frequency pseudo signal, and sends a false strobe emission control signal to the strobe device. There is a possibility that an error will occur in which the strobe light is emitted at the wrong timing and the subject passage sensor erroneously detects the strobe light again. However, according to the present invention, a means for removing a high frequency false signal is provided. By providing the above, only the signal based on the true paper passing output is supplied to the stroboscopic light emitting device and the image pickup device, and the stroboscopic light emission timing is normally maintained even when the conveyance cycle of the subject fluctuates, and the reliability of the image pickup is improved. It is further enhanced.

[0017]

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

[0018]

[Embodiment 1] FIG. 1 is a block diagram showing a schematic configuration of a video recording apparatus to which an image pickup apparatus according to an embodiment of the present invention is applied. With reference to FIG. 1, the video recording apparatus of the present embodiment is
It consists of a transport system, an imaging system, and a recording system.

The transport system transports the form 37 (one of the subjects 1) between them and two rollers 39 that rotate in opposite directions, and a paper sensor that detects the passage (vertical position) of the form 37 being conveyed and falling. 38, two sheets of glass 40 that are parallel to each other and have the same height, through which the form 37 falling between them passes,
It is composed of rollers 41 that rotate in opposite directions and that sandwich and convey the form 37 that has passed between 40. The distance between the two glasses in the horizontal direction is about 1 cm.

The image pickup system includes a strobe 21 provided so as to illuminate a form 37 which emits light and passes through the glass 40 while freely falling, and a CCD camera (electronic image pickup camera) 22 for taking an image of the form illuminated by the strobe light emission. And a motor control signal to the motor driving device of the roller 39 (and the roller 41) and a strobe emission control signal to the strobe 21,
An image pickup control signal is output to the D camera (electronic image pickup camera) 22, a motor operation signal is output to a motor driver that controls the rotation of the roller 39, and a subject detection signal is output from the paper sensor 38 via a low pass filter (LPF) 46. Entered, CC
A system control circuit 25 to which an image pickup operation signal is input from a D camera (electronic image pickup camera) 22 is provided.

The recording system is provided with a recording device 60 for recording an electric signal based on an image picked up by the CCD camera 22 on a recording medium according to a timing signal from the system control circuit 25.

The paper sensor 38 is composed of, for example, a light-emitting portion and a light-receiving portion which emit weak light at positions where the light-emitting element and the light-receiving element are separated from each other by a predetermined distance and sandwich the paper (subject 1, the form 37). It is composed of a photo interrupter and the like, and judges the presence / absence of paper by detecting the interruption of light by the paper (subject 1, the form 37) (paper is present at the time of interruption and paper passage).

In the video recording apparatus, the motor driver 51 is operated by the roller in response to an operation command from the system control circuit 25.
39 is rotated to start continuous supply and transportation of the form 37. The form 37 is sandwiched by rollers 39 which rotate in the reverse direction, and is freely dropped downward. The paper sensor 38 detects the free-falling form 37 that has entered the sensing area. While detecting the form 37, the paper sensor 38 outputs a subject detection signal to the system control circuit 25 via the low-pass filter 46. System control is performed at the timing when the form 37 exists in the image pickup area (the center of the angle of view of the CCD camera) between the two glasses after a predetermined period of time has passed since the form 37 dropped further out of the sensing area of the paper sensor 38. The circuit 25 issues a strobe emission command to the strobe 21, and the strobe 21 emits light to illuminate the subject. The system control circuit 25 is further CC
Issue an imaging command to the D camera 22 and CC immediately after strobe light emission.
The D camera 22 takes an image of the form 37 irradiated with the strobe light. The image pickup data of the CCD camera 22 is sent to the recording device 60 and recorded according to the timing signal output from the system control circuit 25. The image-captured form is collected by passing between the rotating rollers 41. Such a form
The transport, imaging, and collection of 37 are continuously performed at high speed. Although only one CCD camera 22 and one strobe 21 are shown in FIG. 1, in order to actually image the front and back surfaces, C
Two CD cameras 22 and two strobes 21 are arranged at positions facing each other with the form 37, which is the subject, as the center line.

When the transportation speed of the form 37 is about 1 m / sec and the length of the form is about 10 cm, the paper sensor 38 has a sensing area of 1 m / sec.
The time for which one sheet 37 exists is 0.1 seconds, and the paper sensor 38
The output will be "with paper" for about 0.1 seconds. On the other hand, the flash 21 has a short flashing time of 0.001 second.

FIG. 2 is a block diagram showing the arrangement of an image pickup apparatus in a video recording apparatus according to an embodiment of the present invention, particularly a low pass filter 46.
It is a block diagram showing a peripheral circuit.

With reference to FIG. 2, the image pickup apparatus is provided with a subject 1.
A paper sensor 38 that detects a (form 37) and outputs a subject detection signal, and is composed of a light emitting diode and a phototransistor (light receiving unit); and a buffer 45 that inputs, amplifies, and outputs the subject detection signal output from the paper sensor 38. And the low-pass filter 46 that outputs the low-pass filter output signal that outputs the low-pass filter output signal that is obtained by cutting the high-frequency component of the amplified subject detection signal, and the low-pass filter output signal that the low-pass filter 46 outputs. As input,
Waveform shaping circuit 47 that outputs waveform shaped signal
(Schmitt trigger circuit), the one-shot circuit 48 (light emission timing generation circuit) that outputs the strobe light emission control signal of a predetermined pulse by inputting the waveform shaping signal output from the waveform shaping circuit 47, and the one shot circuit 48 output A strobe 21 for receiving a strobe light emission control signal to emit light at a predetermined timing based on the strobe light emission control signal, and an imaging device (CCD camera 22) not shown. In the low pass filter 46, the capacitors and resistors are appropriately selected according to the desired cutoff frequency (fc). In addition, buffer 45
The operational amplifier of the low-pass filter 46 may be omitted in consideration of cost reduction. Also in this case, the same effect can be obtained by selecting the capacitor and the resistor according to the desired cutoff frequency (f _c ).

In the image pickup device, the output of the paper sensor 38 is
The emitter follower is output and input to the low-pass filter 46 via the buffer 45 including a voltage follower.

The output of the low-pass filter 46 has its DC component removed and is input to the waveform shaping circuit 47. The waveform shaping circuit 47 is composed of Schmitt trigger circuits cascaded in two stages.

The waveform shaping circuit 47 waveform-shapes the output signal of the low-pass filter into a rectangular wave. Wave shaping circuit 47
The one-shot circuit 48 outputs a pulse (strobe light emission control signal) of a predetermined width by using the edge of the rectangular wave output by the strobe 21 as a trigger, and the strobe 21 emits light based on this pulse, and the image pickup device (the CCD camera 22 in FIG. 1). ) Captures an image of subject 1 (form 37) exposed to strobe light.

That is, the output of the paper sensor 38 causes the flash 21
The light emission timing and the image pickup timing are also controlled.

FIG. 3 is a signal waveform of each part of the image pickup device shown in FIG. 2 for explaining the operation of the image pickup device in detail.
3A and 3B are waveform diagrams showing the output signal of the low-pass filter 46 and the lower part are the object detection signals output by the paper sensor 38 (the time axis is common), and FIG. 3C is the object. The output signal of the waveform shaping circuit 47 when the strobe 21 is made to emit light without sending 1 (form 37) and does not pass through the low-pass filter 46 is compared with the time axis in FIGS. 3 (A) and 3 (B). It is a waveform diagram which expands and shows. However, FIG. 3 (A)
Is a low-pass filter 46 whose removal frequency is lower than that in FIG.
Is used.

Referring to FIG. 3, in the image pickup apparatus, when the light receiving portion of the paper sensor 38 receives the light of the light emitting diode, it is at a high level (it is judged that there is no paper and paper passes), and when it is obstructed, it is at a low level (paper is present, paper is passed) It outputs a subject detection signal (determined as passing). The period during which the subject 1 (form 37) is in the sensing area of the paper sensor 38 (period during which light reception is interrupted) is shown in FIG.
Is about 40 ms, and is about 30 ms in FIG. 3B, and the subject 1 (form 37) is periodically conveyed to the image pickup system and is imaged by strobe emission.

Referring to the lower part of FIG. 3A, the paper sensor 38
The paper sensor 38 outputs a pulse with a width of about 40 ms for detecting true paper and a pseudo signal with a short pulse width of about several μm that is synchronized with strobe light emission with a period substantially the same as the pulse signal for detecting true paper. .

Referring to the lower part of FIG. 3B, the paper sensor 38
Outputs a pseudo signal having a short pulse width of about several μm which is synchronized with the strobe light emission having substantially the same period as the pulse signal of the true paper detection, together with the pulse of about 30 ms width of the true paper detection.

Referring to FIG. 3C, the low-pass filter 46 is not provided between the paper sensor 38 and the waveform shaping circuit 47, and the strobe 21 is emitted at a light emission time of about 12 μm without feeding the subject 1 (form 37). When the light is emitted, the waveform shaping circuit 47 outputs a high level (paper-less level, that is, paper passing) triggered by strobe light emission. This is the paper sensor 38
However, the pseudo signal (false subject passing signal) is output even though the irregularly reflected light emitted from the strobe is received and the subject 1 in FIG. 2 (the form 37 in FIG. 1) is not detected.

When the strobe 21 receives a signal relating to the pseudo signal (fake subject passage signal) output from the paper sensor 38, a deviation occurs in the light emission timing of the strobe 21 and normal photographing is not performed. In order to prevent such a phenomenon, referring to FIG. 2, a low pass filter 46 is provided between the paper sensor 38 and the waveform shaping circuit 47.

The output signal of the low-pass filter 46 shown in the upper part of FIG. 3 (A) (and FIG. 3 (B)) has its high frequency band cut off, and the lower part of FIG. 3 (A) (and FIG. 3 (B)) shows. Since the very short pulse (pseudo signal) appearing in the output of the paper sensor 38 shown in the figure is removed, the erroneous detection of the paper sensor 38 caused by the above strobe emission affects the strobe emission timing and the imaging timing. Do not give.

As described above, since the low-pass filter 46 eliminates the erroneous detection signal of the paper sensor 38 caused by the strobe light emission, the strobe light emission is normally synchronized with the paper feed, and the subject 1 (form 37) is in the image pickup area. It only happens when it exists,
The CCD camera 22 that performs an image capturing operation in synchronization with strobe light emission captures a normal image. Therefore, detecting the position of the subject,
The timing of light emission and imaging is always maintained normally, and the pseudo signal causes the light emitting device to continuously emit light at an abnormal speed,
By preventing an abnormal phenomenon in which the image pickup apparatus continuously picks up images at an abnormal speed, the reliability of image pickup recording is further enhanced.

The image pickup apparatus according to the present embodiment is particularly effective for high-speed image pickup, or when the image pickup and light emission timings are not fixed because the object supply speed or the object shape is different.

Further, in the apparatus for conveying an object at a high speed and stroboscopically photographing as in the present embodiment, when an optical sensor is used for detecting the position of the object, even if strong strobe light is emitted, the optical sensor (paper sensor) By preventing the erroneous detection of the paper due to the malfunction, the high-speed and highly reliable image pickup is realized.

In the image pickup apparatus of this embodiment, when the conveyance speed of the form 37 (one of the subjects 1) is set to about 1 m / sec and the length in the falling direction of the subject is set to about 10 cm, the subject in the sensing area of the paper sensor 38 is set. The transit time, that is, the output of the paper sensor 38 is about 0.1
"Paper present" for seconds. On the other hand, a flash with a short flash time
If the light emission time of 21 is about 0.001 seconds, the detection time is 0.001 seconds even if the strobe light enters the paper sensor 38, and the cutoff frequency (removal frequency) of the low-pass filter 46 is set to about 40 to 200 Hz. As a result, it is possible to preferably eliminate erroneous detection of the paper sensor 38 due to stroboscopic light emission.

[0042]

Embodiment 2 FIG. 4 is a second embodiment of the present invention and is a block diagram for explaining the schematic structure of the entire magnetic recording / reproducing apparatus to which the video recording apparatus of one embodiment of the present invention is applied.

Referring to FIG. 4, the magnetic recording / reproducing apparatus comprises a carrying / imaging system, a system control system and a magnetic recording / reproducing system.

The transport / imaging system includes a transport mechanism 20 for transporting a subject and dropping it into an image capturing range (between two glasses), and a strobe 21 for emitting light when the subject is located within the image capturing range.
And two CCD cameras 22 for picking up an image of a subject in synchronization with the emission timing of the strobe 21.

The transport mechanism 20 is provided with a subject passage sensor (see the paper sensor 38 in FIG. 1) not shown in the drawing, and starts the transport of the subject in response to a transport mechanism operation signal from the system control circuit 25. Detects the passage (fall) of the subject due to conveyance, outputs a strobe light emission signal to the strobe 21 at a predetermined timing (the subject is within the image pickup range), and also outputs an image pickup signal to the CCD camera 22. The strobe 21 emits light after a lapse of a predetermined time from the detection of passage of an object by the object passage sensor, and the two CCD cameras 22 are set to 2
Both sides of a subject irradiated with stroboscopic light while falling between a pair of glasses (see glass 40 in FIG. 1) are imaged, and images are temporarily stored as electric charges.

The system control system includes a system control circuit 25 for controlling the entire video magnetic recording / reproducing apparatus,
An operation panel 23 (operation unit) that sends an operation command to the system control circuit 25, a memory 24 that is connected to the system control circuit 25 and is capable of temporarily storing image data and providing main power, and C
A / D conversion circuit 32 for A / D (analog / digital) converting the electric current due to the electric charge captured by the CD camera 22 and outputting a digital video signal, and a display memory for inputting the digital video signal and storing it as image data 26, and a SSG 33 (Sync Signal Ge) for generating a conversion timing signal of the A / D conversion circuit 32 and a writing timing signal of the digital video signal output from the A / D conversion circuit 32 to the display memory 26.
a synchronizing signal generator), an LCD display 27 for reproducing image data by taking in image data and reproduced image data from the display memory 26 via the system control circuit 25, a printing device 36 for printing the reproduced image, Consists of.

The system control circuit 25 sends a subject transfer start command to the transfer mechanism 20 via the transfer mechanism control circuit 31 when an operation command for the entire video magnetic recording / reproducing apparatus is input via the operation panel 23, and a display memory is displayed. The image data stored in the display memory 26 is captured, the image data is temporarily stored in the memory 24, and the output of the LCD display 27 is controlled to control the magnetic recording and reproduction of the image data stored in the display memory 26.

The magnetic recording / reproducing system includes a magnetic recording / reproducing servo circuit 35, a magnetic recording / reproducing mechanical deck 28, a cassette 30, and
An A / D / D / A (analog / digital / digital / analog) conversion circuit 34 for converting the digital video signal stored in the display memory 26 into the analog video signal and reproducing the analog video signal. And a magnetic recording / reproducing processing unit 29.

The magnetic recording / reproducing servo circuit 35 receives the recording / reproducing command from the system control circuit 25 and instructs the magnetic recording / reproducing processing section 29 to perform the magnetic recording / reproducing. The magnetic recording / reproducing processing unit 29 magnetically records the image data from the display memory 26 on the cassette 30 by the magnetic recording / reproducing mechanical deck 28 during D / A conversion during recording, and via the magnetic recording / reproducing mechanical deck 28 during reproducing. The magnetic recording recorded on the cassette 30 is reproduced and output to the display memory 26 through A / D conversion.

The display memory 26 has a capacity capable of storing image data of a plurality of screens, and the magnetic recording data corresponding to these image data is stored in the cassette 30 without any space (empty track or empty area in one track). Recorded).

The video magnetic recording / reproducing apparatus includes a transport mechanism 20 having a subject detection sensor (paper sensor) 38, a buffer 45 according to the first embodiment of the present invention, a low-pass filter 46, a waveform shaping circuit 47, and a one-shot circuit. Equipped with 48. Alternatively, the transport mechanism control circuit 31 or the system control circuit 25 may be provided with these.

The reliability of video (image) recording is improved by applying the image pickup apparatus of one embodiment of the present invention to a video (image) magnetic recording / reproducing apparatus for picking up and magnetically recording such a video (image). Therefore, the apparatus of this embodiment is suitable for high-speed recording of important forms such as checks and bills.

Although the present invention has been described with reference to the above embodiment, the present invention is not limited to the above embodiment,
It includes various aspects according to the principle of the present invention.

[0054]

As described above, according to the image pickup apparatus of the present invention, a high-frequency pseudo signal output from a sensor for detecting an object, which is caused by light emission for illuminating and imaging the object, is formed by a simple circuit. To be removed. Therefore, the timing of the detection of the subject by the sensor and the timing of light emission and imaging are always maintained normally, and the pseudo signal causes the light emitting device to continuously emit light at an abnormal speed, or the imaging device continuously images at an abnormal speed. By preventing such an abnormal phenomenon, the reliability of the imaging record is further enhanced. The present invention is particularly effective in high-speed imaging, or when the supply speed of the subject or the shape of the subject is different so that the cycle of the imaging and light emission timing is not fixed.

Further, by applying the present invention to a device which conveys a subject at a high speed and drops between the sensors for detecting the subject to photograph a strobe, even if a strong strobe light is emitted, the subject detection sensor can detect. Since it is possible to prevent erroneous detection of a subject based on a malfunction, high-speed and highly reliable imaging is realized.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating a schematic function of video recording according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of an image pickup apparatus in a video recording apparatus according to an embodiment of the present invention, particularly a circuit around a low-pass filter.

3 is a signal waveform of each part of the image pickup device for explaining the operation of the image pickup device of FIG. 2 according to an embodiment of the present invention;
The upper stages of (A) and (B) are waveform diagrams showing the output signal of the low-pass filter, and the lower stage is a waveform diagram showing the subject detection signal output by the paper sensor (the time axis is common), and (C) is the subject (form).
FIG. 7 is a waveform diagram showing an output signal of a waveform shaping circuit when a strobe is caused to emit light without feeding and without passing through a low-pass filter, in which the time axis is enlarged as compared with (A) and (B). Note that (A) uses a low-pass filter having a lower removal frequency than (B).

FIG. 4 is a block diagram showing a schematic configuration of an image magnetic recording apparatus to which the magnetic recording apparatus according to the first embodiment of the present invention is applied, according to the second embodiment of the present invention.

[Explanation of symbols]

1 subject 20 transport mechanism 21 strobe 22 camera (imaging means) 23 operation panel 24 memory 25 system control circuit 26 display memory 27 LCD (liquid crystal) display 28 magnetic recording / playback mechanical deck 29 magnetic recording / playback processing section 30 cassette 31 transport mechanism control circuit 32 A / D (Analog / Digital) conversion circuit 33 SSG (Sync Signal Generator) 34 A / D / D / A (Analog / Digital / Analog /
Digital / conversion circuit 35 Recording / playback servo circuit 36 Printing device 37 Form 38 Paper sensor (subject detection sensor, optical sensor) 39 Conveying roller 40 Glass 41 Conveying roller 45 Buffer 46 Low pass filter 47 Waveform shaping circuit (Schmitt trigger circuit) 48 One shot Circuit (timing generation circuit) 60 Recording device

Claims (3)

[Claims] 1. A sensor for detecting a subject, a light-emitting device that receives an output of the sensor as an input, and emits light according to the output of the sensor, and a means for capturing an image of the subject, the output of the sensor and the An image pickup apparatus comprising means for removing a predetermined high frequency component of an output signal of the sensor between the light emitting apparatus and an input of the light emitting apparatus. 2. An optical sensor that detects the position of the subject and outputs a subject position detection signal; a strobe light emitting device that receives the output of the optical sensor as input and emits light in accordance with the output of the optical sensor; A subject position detection signal output from the sensor is input, a buffer that amplifies and outputs, and the amplified subject position detection signal output from the buffer is input, and a predetermined high frequency component of the amplified subject position detection signal is input. A filter for removing, a waveform shaping unit that inputs the output of the filter and outputs a pulse signal by waveform shaping, and a timing generation circuit that outputs a strobe emission control signal according to the output of the waveform shaping unit, A strobe device that emits light based on the strobe light emission control signal output from the timing generation circuit, and an output from the timing generation circuit The image pickup apparatus according to claim 1, further comprising: a camera that takes an image based on a strobe light emission control signal. 3. The image pickup apparatus according to claim 1, wherein the subject mainly comprises a paper member, and the subject falls between the sensors in a substantially vertical direction.