JPS597948B2 - Color display method of PPI video - Google Patents

Description

Detailed Description of the Invention The present invention uses a cathode ray tube with a single electron gun to display signals such as radar images and vector symbols processed by a computer in color on the same cathode ray tube in devices that perform PPI display. This relates to a display method.

Similar conventional devices used a cathode ray tube coated with a single phosphor to display information such as radar images and vectors, so there was a lack of distinguishability between radar images and information such as vectors. Ta.

In order to improve the degree of discrimination between radar images and images such as vectors in PPI display, the present invention uses fluorescent materials with different afterglow characteristics, such as a phosphor with a short afterglow property and a phosphor with a long afterglow property. By using a light object and simultaneously applying a signal with a slow scan rate and multiple signals with a fast scan rate, radar images with a slow scan rate can be observed with a long afterglow emission color, and signals such as vectors with a fast scan rate can be observed. is designed to be observed with a color intermediate between the short afterglow emission color and the long afterglow emission color.

FIG. 1 is a block diagram showing an example of the present invention, in which 1 is a computer, 2 is a vector generator, 3 is a PPI sweep generator, 4 is a deflection amplifier, 5 is a control signal generation circuit, 6 is a video signal amplifier, 7 is a CRT, that is, a cathode ray tube, and its fluorescent surface is coated with phosphors having different afterglow characteristics.

Next, we will discuss the operation.

First, the radar video signal is amplified by the video amplifier 6 and then applied to the cathode of the CRT 70, while the antenna rotation signal is turned into a rotation sweep by the PPI sweep generator 3, and is applied to the deflection coil via the deflection amplifier 4.
It is observed as a PPI screen on a cathode ray tube T as a normal radar video signal.

At this time, the radar image signal is updated every rotation of the antenna, so during that time it is observed in a luminescent color with a long afterglow characteristic.

Here, while the radar image signal is at rest, a sweep signal such as a vector generated by the computer 1 is generated by the vector generator 2 and applied to the deflection coil through the deflection amplifier 4, and the electron beam of the cathode ray tube 7 is transmitted from the computer 1. scan according to the signal.

The brightness of this scanning line is controlled by a control circuit 5.

At this time, if the scan rate of the signal generated by the computer is made much faster than that of the radar image, this signal can be constantly observed on the cathode ray tube in the emission color with the shortest afterglow characteristic.

Note that one scan of a radar image is the time required for one revolution of the antenna, which usually takes about 2 to 3 seconds, and when drawing vectors, etc., data is read from the memory in real time, so the data update rate is in units of m8ee.

Furthermore, Figure 2 is a graph showing the afterglow characteristics when blue and orange fluorophores are used as an example; in this case, the radar signal becomes blue at the moment the electronic beam is applied, and immediately continues to remain orange afterglow. , the vector continues to emit light in a color intermediate between blue and orange because the data is updated many times in real time.

As explained above, in collision prevention devices that superimpose vectors etc. on radar images, the present invention has the advantage of significantly improving the degree of discrimination due to the color display on the PPI screen. Observation-accurate information can be obtained even on the PPI screen.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an actual case of the present invention, and FIG. 2 is a diagram showing afterglow characteristics.

Claims (1)

[Claims] 1 Using a cathode ray tube whose fluorescent surface is coated with phosphors with different afterglow characteristics, radar images and additional signals are irradiated onto the fluorescent surface of the cathode ray tube while changing the scan rate, and the radar signal is transmitted at a slower scan rate. A color display method for PPI video, characterized in that the additional signal is emitted in a color intermediate between the light emission color with short afterglow characteristics and the light emission color with long afterglow characteristics by increasing the scanning rate of the additional signal.