| 摘要 |
PURPOSE:To generate a good a grey chart signal suitable for vision by generating a voltage applied by a specific expression. CONSTITUTION:To terminals 1a, 1b, a clock signal obtained by equally dividing one horizontal period into 13 steps and a clock signal for every one vertical period are respectively supplied, they are selected by a switch 2, supplied to an address counter 3 and an address from the counter 3 is supplied to a ROM 4. A coefficient applied by the expression I is written in the ROM 4, the address corresponding to a step value (x) is supplied, the corresponding coefficient is read, the read coefficient is supplied to an amplifier 6 through a D/A converter 5, a standard voltage Vo is multiplied in the D/A converter or the amplifier 6, a signal from the amplifier 6 is fetched to an output terminal 8 and supplied to an image receiving tube or the like. Since the grey chart signal is formed at an equal interval visually, an adjustment is effectively and easily carried out.
|
