JPS62126783U - - Google Patents

Description

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of an image display device according to this invention, FIG. 2 is a diagram showing an example of its display state, and FIG. 3 is a waveform diagram for explaining the operation of the marker signal generating portion of FIG. 2. 4 is a block diagram showing an example of a portion where a marker signal is written, FIG. 5 is a block diagram showing an example of the differentiation circuit 56, FIG. 6 is a diagram showing another example of marker display, and FIG. 8 is a block diagram showing another example of the marker display signal generation and its write generation part, FIG. 9 is a block diagram showing still another example, FIG. 9 is a diagram showing another example of the marker, and FIG. FIG. 11 is a block diagram showing another example of marker signal insertion. FIG. 11 is a block diagram showing a circuit for obtaining a trigger signal in a shift operation. 11: Cathode ray tube, 12: Main oscillator, 13: Frequency divider, 16: Main memory, 22: Trigger terminal, 23:
Input signal terminal, 18: Color conversion circuit, 24, 3
6: Buffer memory, 55: Marker generation frequency divider, 56: Differential circuit, 57: Gate, 54: Marker.

Amendment September 24, 1986 The scope of claims for utility model registration is amended as follows.

[Scope of utility model registration request] Scanning and synchronization of the display surface of a scanning type display cathode ray tube
to read out the digital main memory and read out the readout output.
is supplied to the display cathode ray tube as a display signal,
Input the detection signal from the fish finder into the main memory above.
Each time, one end of the display surface of the above display cathode ray tube is
The input detection signal is displayed as one display line.
At the same time, the old display line is sequentially shifted to the other end.
, and the oldest detection signal is deleted from the main memory above.
An image display device for a fish finder, The above display cathode ray tube is a color cathode ray tube, The above detection signal is supplied, and this is converted into a digital signal.
an AD converter that converts into Generates a low-speed clock that operates the AD converter.
a low-speed clock generator that generates The digital signal from the AD converter above is
To MoriForwardfaster than the above slow clock for
A high-speed clock generator that generates a high-speed clock
, To read the above main memory read clock
The read clock generator anda color conversion circuit that converts a digital signal indicating the level of the detection signal read from the main memory into a corresponding color signal and supplies the same to the color cathode ray tube;be equipped with
Image display device for fish finders.

Claims (1)

[Claims for Utility Model Registration] Reading out a digital main memory in synchronization with the scanning of the display surface of a scanning cathode ray tube for display, and supplying the readout output to the cathode ray tube for display as a display signal,
Every time a detection signal from the fish finder is input into the main memory, the input detection signal is displayed as one display line on one end of the display screen of the display cathode ray tube, and the old display lines are sequentially replaced with the other display lines. An image display device for a fish finder that shifts the detection signal toward the end and erases the oldest detection signal from the main memory, the AD converter being supplied with the detection signal and converting it into a digital signal, and the AD converter. a low-speed clock generator that generates a low-speed clock to operate the device; a high-speed clock generator that generates a high-speed clock faster than the low-speed clock for writing digital signals from the AD converter to the main memory; A read clock generator for generating a read clock faster than the high speed clock for reading a main memory.