KR960015059A - Electronic shutter control circuit and method of camera - Google Patents

Abstract

1. TECHNICAL FIELD OF THE INVENTION The invention described in the claims pertains to electronic cameras and camcorders, and in particular technology for controlling the speed of electronic shutters.

2. The technical problem to be solved by the invention: It solves the limited speed of the electronic shutter in the electronic camera and the distortion of the video signal.

3. Summary of Solution of the Invention: Receives image signal from CCD as input, divides it into several DC levels, and divides it into low speed and high speed shutter and shutter speed stop mode. It generates an electronic pulse for electronic shutter to track at low speed and ultra high speed, and to track at normal low speed and normal high speed in order to control an appropriate response speed.

4. Significant use of the invention: Used in electronic shutters of electronic cameras and camcorders.

※ Selectivity 1

Description

Electronic shutter control circuit and method of camera

As this is a public information case, the full text was not included.

Claims (11)

An electronic shutter control circuit of a camera, comprising: pulse period setting means for setting an electronic shutter pulse of a predetermined period corresponding to a predetermined count value counted as a basic clock, and reading charges of an image signal accumulated in an image pickup device of the camera; Electronic shutter pulse counting means for counting the number of electronic shutter pulses output from the pulse period setting means during the readout pulse period corresponding to one field section, and for determining the response speed and speed mode of the electronic shutter. Electronic shutter speed determining means for counting up and down counting the first clock signal and the second clock signal corresponding to the brightness level, the number of the electronic shutter pulses counted by the pulse counting means from the readout pulse, and the electronic shutter speed determination By setting the window period until the value counted by the means coincides, the electronic shutter pulse is output within the electronically set window period. An electronic shutter control circuit comprising a shutter speed variable stage. 2. The apparatus of claim 1, wherein the pulse period setting means comprises: a counter unit for predetermined counting with a system basic clock, a decoder unit for decoding a counting value of the counter unit into a binary signal having a predetermined period, and a binary signal of the decoder unit. An electronic shutter control circuit comprising a latch unit for outputting an electronic shutter pulse by a first edge and a second edge. 3. The electronic shutter pulse counting means according to claim 2, characterized in that the electronic shutter pulse counting means comprises a counter which is initialized by the readout pulse and counts for one field section of the video signal in response to the electronic shutter pulse of the latch unit. Electronic shutter control circuit. The apparatus of claim 3, wherein the electronic shutter speed determining unit comprises: a comparison unit configured to compare the magnitude of the brightness of the video signal to one or more preset reference voltages, and output one or more comparison signals; And a counting unit configured to decode the comparison signal and output a counting control signal and a clock control signal, and a counting unit performing up and down counting with a predetermined clock applied according to the counting control signal and the click control signal of the decoding unit. Electronic shutter control circuit. 5. The apparatus of claim 4, wherein the comparator comprises: a first comparator for comparing the video signal with a first reference voltage preset for the electronic shutter to operate as a fast response fast shutter; and the electronic shutter as a slow response fast shutter. A second comparator comparing the video signal with a second reference voltage preset for the operation of the second shutter; and a third comparing the video signal with the third reference voltage preset for the operation of the electronic shutter by the slow response low speed shutter And a comparator and a fourth comparator for comparing the video signal with a fourth reference voltage which is preset for the operation of the high-speed response low-speed shutter. The electronic shutter control of claim 4, wherein the decoding unit further comprises a decoder configured to set a limit value of the high speed shutter and a low speed shutter of the electronic shutter according to a counting setting value of the counting unit. Circuit. The pulse count number comparison unit according to claim 1, wherein the shutter speed variable stage compares the electronic shutter pulse and the value counted by the electronic shutter speed determining means during one field in the electronic shutter pulse counting means to generate a pulse in a matched state. And a window setting unit configured to set a window section by latching between the readout pulse and the pulse output from the comparator. 6. The electronic shutter control circuit according to claim 5, wherein the decoder of the decoding unit is a decoder which sets the low speed shutter and the high speed shutter threshold to a range of 1/60 to 1/50000 seconds. 7. The apparatus of claim 6, further comprising a logic operation unit configured to logically perform a window setting output of the window setting unit, an electronic shutter operation on / off switch signal, and an electronic shutter pulse of the pulse period setting unit, and output a variable electronic shutter pulse. Electronic shutter control circuit, characterized in that. In the electronic shutter control circuit, the high speed shutter and the low speed shutter information, the high speed response and the low speed response information are compared by comparing the brightness level of the video signal from the image pickup device with preset first, second, third and fourth reference voltages. Outputting first clock and second clock information corresponding to the high speed and low speed response information states of the comparing means, and outputting up / down counting information corresponding to the high speed and low speed shutter information states, respectively. The electronic shutter is variable by performing counting according to the up / down counting information in response to the first clock and the second clock information of the information decoding means for the information decoding means and the electronic shutter operation of tracking the brightness of the image pickup means. An electronic shutter control circuit comprising a counting means for outputting control information. A method of controlling an electronic shutter of a camera, comprising: a pulse period setting step of setting an electronic shutter pulse of a predetermined period corresponding to a predetermined count value counted as a basic clock, and occurring in the pulse period setting step of one field section of an image signal An electronic shutter pulse counting process for counting electronic shutter pulses, an electronic shutter speed determining process for determining a high speed and low speed shutter mode, a high speed response and a low speed response mode in response to a brightness level of the video signal, and the electronic shutter speed determination And a shutter speed variable process of varying an electronic shutter operation speed of a predetermined one field section corresponding to the pulse counting process in response to the shutter mode and the response mode determined in the process. ※ Note: The disclosure is based on the initial application.