KR970007406B1 - Electronic shutting system for image -scanners - Google Patents

Abstract

An electronic shutting system of image scanner wherein : a switching gate transistor(SQ) is connected between a photodiode(PD) and a power supply(Vcc); the controlled voltage of a variable resistor(VR1) is converted to code through a ROM(6) after it is converted to digital data by an A/D converter(2) to establish prescribed number of horizontal clocks; horizontal clocks(Hi-Hi) are counted by a counter(7) resetted to control pulse(PG); and a comparator(4) compares said established and counted horizontal clocks to output shutting pulses(SP) and then to control the gate power of said switching gate transistor(SQ); is disclosed. Thereby, it is possible to vary the exposing time.

Description

Electronic Shuttering System of Image Scanner

1 is a structural circuit diagram of a conventional image scanner.

2 is a circuit diagram of an image cell of the present invention.

3 is a configuration diagram for driving the image scanner of the present invention.

4 (a) and 4 (b) are time charts of the pulse generator and the shutter pulse of the present invention.

* Explanation of symbols for main parts of the drawings

1: Signal output part 2: A / D converter

3: rom 4: comparator

5: oscillator 6: pulse generator

7: Counter 8: Image Scanner

9: Current source PD, PD11-PDij: Photodiode

C, C11-Cij: Capacitor

GQ, GQ11-GQij: Precharge Gate Transistor

Q11-Qij: Vertical Gate Transistor

SQ: Switching Gate Transistor

VR1: Qn1-Qni: Variable gate transistor

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a VCR camera, and more particularly, to an electronic shuttering system of an image scanner that enables the exposure time of a scanner to be adjusted to less than l / 30 sec or 1/50 sec.

In the conventional CDD image scanner, as shown in FIG. 1, one image cell ce11 is used for a light receiving photodiode PD11, a storage capacitor C11, and a precharge. A gate transistor (GQ11) and a gate transistor (Q11) for the vertical mode, and the cells are arranged horizontally N and vertically M through the matrix shape, the image is moved vertically, each gate transistor for the horizontal mode It is configured to be transmitted to the signal output unit 1 through (Qn1-Qni), the vertical clock (V1-Vi) is supplied to the gate of the vertical gate transistor (Q11-Qij), the gate transistor for the precharge GQ11 The pulse PG, which becomes high potential once every 1 V, is applied to the gate of -GQij.

According to the conventional technology of the image scanner configured as described above, when an image point is imaged on the photodiode PD11 in one cell, the power Vcc proportional to the amount of light is stored in the condenser C11, and the storage time is the interval of the pulse PG. For NTSC, the exposure time is 1/30 seconds.

In this way, the image point stored in the capacitor C11 is transmitted through the charge gate transistor GQ11 by turning on the precharge gate transistor GQ11 at the moment when the pulse PG becomes the high potential in the vertical image loading state. In this case, when the vertical clock signal V1 is supplied at high potential, the image point is vertically equalized by turning on the vertical gate transistor Q11.

Therefore, as the remaining cells perform the same function as described above, the stored image is vertically moved through the supply of the pulse PG and the supply of the vertical clocks V1 -Vi, and the horizontal clocks H1-Hi become high potential. As the horizontal gate transistors Qn1 to Qni are turned on, the vertically shifted image is transmitted to the signal output unit 1 through horizontal shifting.

In other words, the transmission path of the image video signal is supplied through the vertical clocks V1-Vi and the horizontal clocks H1-Hi. Qn1? Qn2? Qn3? The image is scanned as it is transmitted to the signal output unit 1 as follows.

However, in the conventional image scanner as described above, since the exposure time of the image cell becomes constant, when the still image is recorded by recording an image signal when photographing a fast-moving subject, there is a defect that the clear image is not displayed.

In view of such a conventional defect, the present invention electronically controls the received light of the photodiode, and adjusts the exposure time of the image scan to 1/30 sec or 1/50 sec or less, thereby photographing a fast-moving subject. An electronic shuttering system of the image scanner is made possible, which will be described in detail with reference to the accompanying drawings.

2 is a circuit configuration diagram of an image cell of the present invention, as shown therein, after the image image processed through the photodiode PD connected to the power supply Vcc side is stored in the condenser C to control the pulse PG. An image scanner configured to be applied to a vertical gate transistor Qij controlled by a vertical clock Vi through a precharge gate transistor GQ by means of: an anode of the (Vcc) side and the photodiode PD. The switching gate transistor SQ is connected in between, and the shuttering pulse SP is applied to the gate side thereof to control the exposure time.

3 is a configuration diagram of the driving of the image scanner of the present invention, and as shown therein, the value of the current source 9 adjusted through the variable resistor VRl is digitally converted through an analog (A) / digital (D) converter. After conversion into data, the code is converted into a code through the ROM 3 to set the number of horizontal clocks at the terminal D1 of the comparator 4, and the pulse generator 6 outputs the image scanner ( 8, a horizontal clock Hi, a vertical clock Vi, and a pulse PG are supplied to the terminal 8, and the terminal D2 of the comparator 4 is counted after the counter 7 is counted. ) Is compared with the set number of horizontal clocks Hi, and the output thereof provides a shuttering pulse SP to the image scanner 14 to output a vertical image signal.

4 (a) and 4 (b) are time charts of the pulse generator and the shutter pulse of the present invention. As shown therein, the relationship between the control pulse PG and the shutter pulse SP of the image scanner 14 is shown. will be.

Referring to the effects of the present invention configured as described above are as follows.

First, as shown in FIG. 3, as the output of the oscillator 5 drives the pulse generator 6, the horizontal clock signal Hl-Hi, the vertical clock signal V1-Vi, As shown in Fig. 4A, a control pulse PG having an exposure time of l / 30 second is supplied.

At this time, as the control pulse PG resets the counter 7 and supplies a clock by the horizontal clocks H1-Hi, the number of the horizontal clocks H1-Hi is counted, and then the terminal of the comparator 4 is counted. Is applied to (D2).

On the other hand, the consumer adjusts the variable resistor VRl to set a desired exposure time. The adjustment of the variable resistor VRl becomes the voltage change of the contact point A, and the voltage thereof is changed through the A / D converter 2. After conversion to digital data, the code is converted into a code through the ROM 3 to set the number of horizontal clocks H1-Hi at the terminal D1 of the comparator 4.

Here, when the number of horizontal clocks of the terminal Dl of the comparator 4 is larger than the counted number of the terminal D2, it means that it is not yet time to expose the shutter pulse SP. As shown in Fig. 1, when the image scanner 8 is driven at a low potential and the number of terminals Dl is smaller than the number of coefficients of the terminal D2, it means that it is time to expose the shutter pulse SP. As shown in FIG. 4 (b), the high potential is driven to drive the image scanner 8.

In this manner, as shown in FIG. 2, the shuttering pulse SP is input to the gate side of the switching gate transistor SQ, and the shuttering pulse SP is shown in FIG. As described above, when the potential becomes high, the switching gate transistor SQ is turned on, and thus a charge amount proportional to the amount of light emitted to the photodiode PD is accumulated in the capacitor C, thereby operating normally.

At this time, when the shuttering pulse SP becomes low, the switching gate transistor SQ is turned off to cut off the power supply Vcc, and thus the image scanning function is not performed.

Therefore, the section in which the shutter pulse SP becomes high potential becomes the actual exposure time, and by adjusting this time interval externally, the exposure time of l / 30 second in the NTSC method is adjusted to 1/50 second or less. . As described in detail above, the present invention has an effect of reproducing a clear image even when photographing a fast-moving subject because the exposure time of the photographing is adjusted small by the power supply control of the photodiode and the number of horizontal clicks.

Claims (1)

The photodiode PD connected to the power supply Vcc side is controlled by supplying the control pulse PG, the vertical clocks V1-Vi, and the horizontal clocks Hl-Hi output from the pulse generator 6 to control the image. In an image scanner in which a cell is configured to transmit an image signal to a transmission line, a switching gate transistor (SQ) is connected between the photodiode (PD) and the power supply (Vcc) side, and the adjustment voltage of the variable resistor VRl is set to AD. It is converted into digital data through the converter 2 and then converted into a code through the ROM 6 to set the number of arbitrary horizontal clocks, and the horizontal clocks are reset through the counter 7 which is reset to the control pulse PG. Counting (H1-Hi), comparing the set number of horizontal clocks and the counted horizontal clocks through the comparator 4 to output the shutter pulse (SP) and then control the gate power of the switching gate transistor (SQ) Characterized in that the exposure time is configured to be variable Electronic shuttering system for image scanners.

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