KR950004888A - Focus zone shift circuit - Google Patents

Abstract

The present invention relates to a focus zone shifting circuit for moving a focus zone when the subject is out of the focus zone.

As described above, the present invention provides a key input unit 10 for inputting a key for moving a focus zone, a key detector 20 for outputting a screen address value changed by key input of the key input unit 10, and a 4fsc frequency. The screen division circuit 30 which compares an address value counted by a reference click with an output address value of the key detection unit and outputs a control signal and a control signal of the screen division circuit 30 in the focus zone of a predetermined region. An integrating circuit 60 for integrating only the video signal and a focus micom 70 for moving the focus zone until the evaluation voltage output from the integrating circuit 60 becomes maximum.

Accordingly, by allowing the main subject or the photographer to move the focus zone around the desired subject according to the focus zone shift key, autofocus can be executed centering on the desired subject no matter where the subject is on the screen.

Description

Focus zone shift circuit

Since this is an open matter, no full text was included.

FIG. 1A is a diagram illustrating one embodiment when a subject is in a focus zone, and FIG. 2B is a diagram illustrating a general embodiment when a subject is out of a focus zone. 2 is a simplified block diagram of a focus zone shifting circuit according to the present invention. FIG. 3 is a flowchart showing an operating state of the screen division circuit of FIG. 4 is a view showing a focus zone moving area of FIG. 2; 5 is a graph showing the operating state of FIG.

Claims (2)

Key input means (10) for inputting a focus island for moving a focos zone to a main subject or a desired subject to be photographed; A key detection stage (20) for outputting an initial screen address value upon system reset or for outputting a screen address value modified by a key input of the key input means (10); Screen dividing means (30) for outputting a control signal by comparing the address c value counted as a reference clock after the initial call by the initialized horizontal synchronizing signal and the vertical synchronizing signal and the output address value of the key detecting means 20 (30). )and; An integrating means (60) for integrating only an image signal in a focus zone of a predetermined portion by a control signal of the screen disabling means (30) and outputting an evaluation voltage in the focus zone area; And a focus micom (70) for moving the focus zone until the evaluation voltage output from the integrating means (60) becomes maximum. 2. The apparatus according to claim 1, wherein the screen dividing means (30) comprises: a serial buffer (31) for screen addresses output from the key detecting means (20); A horizontal synchronizing initialization unit 33 for receiving and initializing a vertical synchronizing time signal synchronized with a predetermined video signal; A vertical synchronization initializer 34 configured to receive and initialize a vertical synchronization signal synchronized with a predetermined video signal; An address counter unit 35 for initializing the horizontal synchronization initializing unit and the vertical synchronizing initializing unit and counting an address with a 4fsc frequency clock reference clock; And a RAM 32 for outputting an integral enable signal or an integral disable signal for controlling the integration of the integration means 60 by comparing the output address of the serial buffer with the output address value of the address counter. Zone shift circuit. ※ Note: The disclosure is based on the initial application.