JPS6243146B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is a color display in which image signals at polar coordinate positions obtained by transmitting periodic pulse energy and receiving the reflected signals are converted into corresponding orthogonal coordinate positions and displayed as a color image with a desired color. It relates to devices, and can be applied not only to radar transceivers, but also to PPI using ultrasonic waves, sector scan type devices, systems using infrared rays, etc. Conventionally, in a display device that displays images obtained by a system with a slow rotational scanning speed such as a radar, consideration must be given to using a light-shielding hood during the daytime or otherwise darkening the surrounding area. Also, the hood cannot be used and monitored by multiple people at the same time. Therefore, in addition to high-intensity display of radar images, there is also a demand for colored displays that allow the content to be easily deciphered and judged as the displayed content becomes more diverse. The present invention is an orthogonal coordinate type color display device for solving the above-mentioned problems, and has a one-screen image memory, and by increasing the number of scans of image information from which image information is repeatedly read, the displayed image can be improved. In addition to high brightness, the following can also be achieved. (1) Displaying color images with colors that correspond to the combination of the video signal strength and designated areas (for example, land and sea) on an arbitrarily divided display image (for example, displaying a color image with three levels of video intensity) If the number of designated areas is 2, a combination of 6 colors can be displayed.) (2) By considering the boundary line that should divide any of the designated areas (for example, the boundary line between land and coastline in the previous example or the boundary line indicating the navigation area for ships) as one of the designated areas, To simultaneously display a color image by converting the line itself into a desired color image and synthesizing it with a color image signal determined in accordance with the combination of a video intensity signal of one term and a specified area. In addition, by replacing the multiplication function conventionally required for orthogonal coordinate conversion with an addition function, it is possible to realize faster and lower cost coordinate conversion, and also display current and past images. Another object of the present invention is to provide an inexpensive color display device that can also display the trajectory of a moving target and also has a simple collision prevention function. First, an embodiment in which the display device of the present invention is used in a radar transceiver will be described with reference to FIG. Antenna 1 is driven by motor 2 at a rate of 10 per minute.
It rotates approximately 33 times, emits high frequency waves with a narrow beam width in the pointing direction, and receives the reflected waves from the target. The rotation angle of the antenna 1 is converted into an electrical signal by a synchro oscillator 3 or the like and sent to the radar indicating device. Further, in the case of electrically scanning the direction, an electric signal corresponding to the beam direction may be generated. The trigger generator 11 determines the repetition period of the radar. This cycle is normally switched in accordance with the display distance range. The modulator 7 is excited by this trigger signal and drives the magnetron 5 via the pulse transformer 6 with a predetermined pulse width. A part of this pulse is also sent to the display as a transmission trigger.
This signal may be a signal synchronized with the timing at which elastic waves or electromagnetic waves are transmitted even in systems using ultrasonic waves or infrared rays. The magnetron 5 generates a high frequency wave corresponding to the driven pulse width, which is radiated into space from the antenna 1 via the transmission/reception switching device 4. The transmission/reception switching device separates the transmitted wave and the received wave and sends them to the receiver with less loss during reception. and lead. In a receiver, an intermediate frequency amplifier 9 mixes the output of a local oscillator 8, for example a Gunn oscillator in a radar, and a received wave and amplifies the signal to a required level.
The output is detected, further amplified if necessary, and then sent as a video signal to a display. In the above description, the system using an ultrasonic transducer that generates elastic waves does not use a local oscillator, but directly amplifies and then detects the waves, so the detailed configuration may be slightly different. Now, to explain the present invention with reference to the illustrated embodiment, its configuration is shown in FIG. 2, and its operation is shown in FIG. 3. These will be explained below. Second
In the figure, a video signal of a polar coordinate position obtained periodically from the radar transmitter/receiver as shown in FIG. The signal is converted into a digital signal by the sampling clock b shown in FIG. 3 at every fixed sampling time. In the present invention, the received signal strength of the laser signal and the display area of the signal are identified and displayed in a desired color, so the quantization level of the quantizer 101 is set to a desired level. The settings may be made so that a color image with colors of . For example, a radar video signal with a voltage amplitude range of 0 to 6V is quantized into four levels at linear intervals, and in descending order of level, red, red,
4 colors: blue, yellow, and black, while outside the designated area, white,
Assuming that the four colors of green, orange, and black are supported, the amplitude of the video signal, the corresponding color, and the sampling data are as shown in Table 1 below.

[Table] Also, in the above example, the quantization level was set at a linear interval for ease of explanation, but this level can be set to the desired reception intensity level for distinguishing by color, such as logarithmic characteristics, square characteristics, etc. It can be anything you like. The time required for a signal such as a radio wave to propagate back and forth through this display range is directly proportional to its propagation distance, so if you want to obtain a fixed number of sampled data regardless of the size of the display range, Quantization can be performed at a sampling rate that is inversely proportional to the distance. In this case, multiple display ranges require multiple corresponding sampling clock signals. Here, the number of samples of the video signal is a constant number N per transmission trigger sweep of the radar device, and the sampled data is quantized in accordance with the level corresponding to the color for each sampling period, and is sequentially quantized. It is transferred to buffer memory 102 or integrator 103. Note that the buffer memory 102 is an integrator 103.
If the operating speed of the sampling clock sufficiently follows the sampling clock, it is unnecessary, and the quantized sampling data is then transferred directly to the integrator 103. Furthermore, in actual use, the boundaries of the arbitrarily divided designated areas, such as the boundaries between land and the sea or shore, or the boundaries indicating safe navigation areas for ships in a bay, can be obtained using the color video signal. A preferred embodiment of the present invention is to combine and display a color image. With such an embodiment, the specified areas divided by the boundary lines are first made clear, and furthermore, the video signals within each divided area are further divided into colors according to their intensity signals and displayed in color. This has the advantage that display information can be identified extremely easily. Furthermore, if the operating speed of the integrator 103 is low, the sampled data is written to the buffer memory 102 and then transferred to the integrator 103.
will be transferred at low speed. Next, details of the operation of this buffer memory 102 will be explained. It is sufficient that one or two buffer memories 102 have a capacity capable of storing the above-mentioned constant number N of sampled data. If buffer memory is 1
In the case of No. However, in the case of long-distance display, if the time required to write the sampled data is large and the desired reading time cannot be secured within the repetition cycle, the second
As shown in the figure, if a buffer memory 102A and a buffer memory 102B are provided and used alternately, sufficient time can be obtained. For this purpose, dual changeover switches S _1A and S _1B are provided, and currently the switch S _1A is connected to the a side and the switch S _1B is connected to the b side, so that the buffer memory 10
A write operation can be performed in parallel to the buffer memory 102A, and a read operation can be simultaneously performed in the buffer memory 102B. Since switching of both switches is necessary every time a transmission trigger occurs, transmission trigger a is input to the video processing timing generator 118 from terminal 2,
From the output, an R/W control signal to both buffer memories is generated as shown in Fig. 3d and d', and a part of this signal controls the switching operation of the double changeover switches _S1A and _S1B , and the buffer memory 102A and 102
Operation control is performed to alternately switch between write operation W and read operation R of B. In this way, the sampled data written to the buffer memory at a writing speed equal to the sampling speed corresponding to each display range is sequentially read out at another desired reading speed, for example, at a reading speed that is constant and unchanged depending on the display range. and is input to the integrator 103. By providing the buffer memory before the integrator 103 in this way, the first writing speed and the second reading speed can be set independently.
The weighting addition circuit and the like in the integrator 103 can be simplified by operating at near-speed and single speed. Integrator 10
3 can operate at high speed, the sampled data will be directly transferred to the integrator 103 for each sampling period, and the buffer memory 102 will be unnecessary.
As mentioned above. The function of the integrator 103 is to obtain a quantum sampling signal with an improved S/N ratio by correlation between periodic signals obtained for each transmission trigger, rather than simply converting a video signal into a quantum sampling signal. . The switch S2 is provided for use by being connected to the side when writing the output of the buffer memory directly to the extraction memory 104 without going through the integrator 103. Normally, when using an integrator, switch S2 is connected to the side, and buffer memory 102A is used.
or 102B is applied to one input of an adder in the integrator 103, and its output is connected to the switch S2 side as the output f of the integrator. The extraction memory 104 receives the output from the integrator 103 or the buffer memory, and when an extraction trigger as shown in FIG. 3g is input, N pieces of data are written one time. Extraction trigger g is 1/n of transmission trigger a
(n is the number of integrations of 1, 2, 3), and the resulting extracted video is shown in FIG. 3h. The video processing timing generator 118 controls the above operations. Further, the video processing timing generator 118 sends a transfer permission signal and an angle sample signal as shown in O and C in the figure to the address generation controller 105 at the same period as the extraction trigger as shown in FIG. 3g. The reading of the transferred video from the extraction memory 104 is performed in synchronization with the writing to the video memory 111, and the transfer can be completed before the next extraction trigger g enters the extraction memory 104.
As shown in Figure i (part of Figure h is enlarged), the data is transferred to the video memory 111 at a sufficiently slow speed, that is, as temporally expanded sampled data. Next, the orthogonal address generation operation for writing to the video memory 111 will be explained. The angle signal from the synchro oscillator 3 of the transmitter/receiver shown in FIG. 1 is inputted from the terminal to an analog angle zagital converter (hereinafter referred to as S/D converter) 107, which outputs the digital angle signal shown in FIG. 3j. obtain. Of course S/D converter 1
07 is unnecessary when directly receiving a digital angle signal. The angle latch 108 stores the output of the S/D converter 107 from the fall of the transfer permission signal O, and holds the digital angle signal until the next fall of the transfer permission signal O. The digital angle signal may be latched at any time after the input of the angle signal j and before the rise of the write signal W, which will be described later, but in the operation explanation shown in FIG. This is an example of a configuration so that In any case, the sampled data to be displayed on the indicator must be displayed correctly at the orthogonal coordinate position converted from its polar coordinate position.
The angle signal as the azimuth angle of the antenna corresponding to the transfer video i, that is, the sampling data outputted from the extraction memory 104 is held in the angle latch 108, and the output angle signal k is sent to the next stage digital resolver 109 at an appropriate timing. The configuration may be such that the voltage is applied to the voltage. Of course, if the rotation speed of the antenna is slower than the transmission trigger period, the angle latch 108 may be omitted. Furthermore, if a certain angular correction is required for the relative angle for reasons such as converting the relative azimuth to the true azimuth, the corrected signal may be employed as the angle signal of the indicator. The digital resolver 109 is obtained in this way and receives the latched angle θi as an input and generates sin θi and cos θi on the output side. Specific examples of the digital resolver 109 include a commercially available ROM and conversion module as a sin/cos lookup table. Now, the relationship between polar coordinates and orthogonal coordinates is that the distance is R, the angle is θi, and the corresponding orthogonal coordinates are x, y
Then, x=R・cosθi(1) y=R・sinθi(2)〓 In equations (1) and (2) given by In this case, the angle θi is constant, and if the sampling unit distance for the distance R is γ, the distance R increases by γ for each sampling data, so now the nth sampling coordinate position is (xn, yn ), then xn=x _o-1 +γ・cosθi(3) yn=y _o-1 +γ・sinθi(4)〓 To further simplify the calculation, set the sampling unit distance γ to 1. If normalization is performed, x _o =x _o-1 + cosθi(5) y _o =y _o-1 +sinθi(6)〓, and only a simple addition operation is sufficient. In order to perform the addition of equations (5) and (6), the previous x _o-
1 and y _{o -1} are stored in respective memory devices, the outputs of these memory devices and cos θi or sin θi are added, and the sum is stored in the respective memory devices as the current x _o and y _o . This operation may be performed sequentially for each unit distance. Accumulator 110 performs this function. This accumulator also has the function of directly storing data Xo and Yo from the outside as shown in Figure 2. The above calculation results are corrected using the values of Xo and Yo, and the coordinate origin is moved to an arbitrary location. You can also. This is called the off-center (OFFCENTER) function. Further, the accumulator 110 may be a general calculator having four arithmetic functions. In this way, the accumulator 11
0 is the accumulation clock l corresponding to the sample unit distance as shown in FIG. 3 from the address generation controller 105 and sinθi,cos from the digital resolver 109.
Rectangular coordinate addresses x _o and y _o of the accumulated results are generated as outputs by inputting the signal θi. When converting polar coordinate system data into orthogonal coordinates and writing it to the video memory 111, the addresses in the center near the coordinate origin will be accessed repeatedly, and necessary information that has been written once will not be erased. ``Methods that equalize the number of accesses between the center and the periphery'' and ``methods that equalize information between the center and the periphery'' are also being considered. In the present invention, an access number controller 106 is provided, and by connecting the switch _S3 , it is possible to equalize the number of accesses between the center and the periphery.
As shown in FIG. 4, an example of the access number controller 106 is to control sampled data on a scanning line in the radial direction of the polar coordinates at every fixed angle in the rotational direction of the antenna or every rotational scanning line number.
The boundary point address between the sampling area indicated by the solid line in the figure and the non-sampling area indicated by the broken line in the figure is set as the position address of the circle in the figure, and the address is stored in advance in the memory built in the access count controller 106. The boundary address data corresponding to each scanning line is read out from the storage device each time each scanning line is started, and is inputted to the address generation controller ₁₀₅ via switch S3. Each time the address generation controller 105 calculates orthogonal coordinates, it determines whether it is a non-sampling area from a coordinate point related to polar coordinates to a boundary address, or a sampling area beyond the boundary address. By controlling ON/OFF the data write signal W as shown in FIG. You can measure the uniformity of the number of times. Further, as the video memory 111, a random access memory (RAM) is used since arbitrary access is normally required. Next, a synchronizing signal for generating and scanning television addresses will be explained. clock generator 1
12 generates clocks necessary for the synchronization signal generator 113, the address generation controller 105, the video memory 111, and the area designation memory 123, and supplies them thereto. The synchronization signal generator 113 has a close relationship with the read address generator 114.
This is because the video data stored in the video memory 111 must be correctly reproduced on the cathode ray tube of the RGB color display 121. Here, the RGB color display 121 independently controls the color of the image projected on the color cathode ray tube using three color signals of R red, G green, and B blue, and displays the desired color. This is a display that can provide color images. As is well known, in televisions, interlaced scanning is used as an electron beam scanning method for cathode ray tubes because it causes less flicker. Also in the present invention, a similar scanning method can be used for electron beam scanning. A synchronizing signal generator 113 generates a horizontal synchronizing signal S and a vertical synchronizing signal T in FIG. 2, as well as signals necessary for a read address. A read address generator 114 generates a memory read address for reading data on the video memory 111 and area designation memory 123 in accordance with the scanning pattern. This is usually constituted by a counter or the like. FIG. 5 shows scanning on a cathode ray tube when interlaced scanning is performed with the number of effective scanning lines set to an odd number and the orthogonal address being the center of scanning. In this example, the scan is sequentially 2
-4-6-8-1-3-5-7-9-2... Regarding the configuration of the video memory, for example, if the display time on the cathode ray tube is 47μs in one horizontal scanning period of a TV, the effective display period is 47μs.
When S is divided into 512 dots and displayed, the read cycle time from the video memory per dot is
It becomes 92nS. However, the readout cycle of existing and easily realized video memories is slow at 250 to 500 μS, so in order to display the contents of the video memory on a television, one readout requires multiple points, for example 16 points (dots). Read the video data at once,
This parallel data may be converted into serial data and displayed on the television indicator. FIG. 6 shows an example of a video memory configured with these considerations in mind. In this figure, 302 is a dynamic random access memory chip. The row selection pulse and column selection pulse are called CAS and RAS, respectively. this
When CAS and RAS are supplied to each chip, the upper UB and lower LB of the address must be switched accordingly. A data selector 306 for this purpose is controlled by the memory controller 301. In this way, the data of the memory cell selected by the addresses UB and LB is transferred to the parallel/serial converter 3.
04. Parallel/serial converter 304 outputs serial data to 0 according to the clock. In this way, high-speed reading is achieved. Address generation controller 105 performs simple writing or reading and rewriting.
A write enable signal WE is generated in accordance with a write signal W as shown in FIG. This is performed by decoder 305. As in the case of a read operation, both address signals UB and LB are supplied, and new data is written into the memory cell according to the data from the I input. Also, when reading before writing,
Before the WE signal is supplied, the 16 data of the memory cells selected by UB and LB are sent to the data selector 303. The data selector 303
Outputs the data of the chip specified by CSB to 0'. Next, switching between the read address and the write address of the video memory 111 will be explained in detail with reference to FIG. Assuming that the indicator display time per dot is 92nS as mentioned above, 92nS x 16 =
If the read cycle is within 1.47 μS, continuous reading can be performed. On the other hand, if the period of the extraction trigger g is 2000 μS and the writing time to the extraction memory is 158 μS (0.617 μS × 256), the data in the extraction memory 104 is processed at least 7.2 μS per piece of data ≒ {(2000 μS −
158 μS)/256}, all sampled data in the extraction memory is written to the video memory 111. This switching operation between writing and reading into the video memory 111 is performed by a synchronizing signal generator 113. That is, when the blanking signal is valid, that is, during the blanking period of horizontal scanning of the television, reading and rewriting or simple writing are performed according to the address from the accumulator 110, and when the blanking signal is invalid, that is, The changeover switch S5 is operated so as to perform reading according to the address from the read address generator 114 during the valid display period. In actual equipment, the average writing speed can be achieved at around 5.86μS/data, so as mentioned above, the writing speed is 7.2μS/data.
S or less, reading/rewriting or simple writing using X _o and _Yo can be executed. Another possible method is to operate the changeover switch S5 every read cycle or every integer multiple thereof. Next, when the switch S4 is on, the large amplitude priority circuit 116 reads data from the address to be written to the video memory 111 when writing the data of the transfer video i from the extraction memory 104 to the video memory 111, The amplitude of the data of the output O' is compared with the amplitude of the data of the transferred video i from the extraction memory 104, and the data with the larger amplitude is adopted as the data to be actually written to the video memory 111. The memory 111 is rewritten. By performing such processing, the data stored in the video memory 111 is transferred to the switch S4.
Image memory 111 from the time of connection to the present
The maximum amplitude of the data written to each address is stored, and the current data is sequentially overwritten on the past data as an image. Therefore, by continuously observing a target whose position changes over time, it is possible to display the movement trajectory of the target, and the time required for observation. The moving speed and movement of the target can be easily determined from the form of the moving trajectory. This is one of the features of the present invention. Read address generator 1 from video memory 111
The video data n read out according to 14 is a digital signal read out from 0 at the timing shown in FIG. 3n. The area designation memory 123 stores and outputs an area determination signal for determining whether the video data read from the video memory 111 is data within a designated area. This area discrimination signal is stored and output. This area discrimination signal is a signal that specifies the conversion method when converting the video signal into a color video signal. Different conversion methods are then applied to convert the desired color signal. The area designation memory 123 has the same address area as the video memory 111 and receives an address signal output from the read address generator 114,
At the same timing as the video memory 111 controlled by the blanking signal and clock signal,
The area discrimination signal is read out. When there are two types of conversion methods for color signals based on this area specification, that is, when the display screen can be divided into two areas and a color image is obtained using a different conversion method for each area, as shown in Table 1. As for the capacity of the area specification memory 123, one bit of data is sufficient for each address value.For example, the area specification memory 123 has 1 in advance for addresses corresponding to the specified area and 0 for other addresses. All you have to do is write it down. In this way,
When the video data read from the image memory 111 exists within the designated area, the area determination signal is 1.
Moreover, when the video data exists outside the designated area, the area discrimination signal becomes 0, making it easy to make a discrimination. Furthermore, if one of the area discrimination signals read out from the area designation memory 123 is used as a boundary line signal of an area to be arbitrarily divided, a boundary line image with a desired color can be created using the color video signal. It becomes possible to synthesize and display the resulting color image. For example, if the areas specified by the area discrimination signals 0 and 1 are adjacent to each other, the linear chain area that is the boundary line between them is regarded as one area, and the area discrimination signal of this area is set to 2. It is determined that In this state, if the color code converter 117 is set to output a color video signal with a specific color when the value of the area discrimination signal is 2, regardless of the video signal strength, the border information can be changed. A color video signal can be easily obtained. Furthermore, if several types of color signal conversion methods are to be designated, this can be done by increasing the number of bits per address in the area designation memory 123. For example, 1
By specifying 2 bits per address, the area can be identified into four types, 0, 1, 2, and 3, based on the value of the area discrimination signal, and each area can be identified using a different conversion method. Color video signals can be obtained. Further, in the area designation memory 123, if the specified area does not change depending on the time, the position of the radar itself does not change, such as a port radar, for example.
If the area of interest is always the same, it may be configured with ROM (Read Only Memory) or the like and predetermined fixed data may be written therein. On the other hand, when the specified area changes from moment to moment, such as in radar images of ships, the area specification memory 123 uses RAM (Random Access
Memory), and the data can be rewritten according to the operation of the ship. In order to perform this data rewriting operation, the computer system 124 controls the ship's course, speed, tidal current direction speed, etc., to calculate changes in the relative position of the topography as seen from the own ship, and based on the results. It is possible to rewrite information in the area specified memory. The color code converter 117 converts the video data n
is converted into a desired RGB drive signal r according to a conversion method determined by the area discrimination signal. This color video signal r causes a desired color display image to be projected on the RGB color display 121. Now, assuming that the input level of each RGB drive signal of the RGB color display 121 is fixed, during this conversion, the value of the video data n is converted into a 3-bit signal with 7 gradations, that is, 7 colors, which differ depending on the area. By arbitrarily selecting this conversion method, the video data can be converted into any of seven colors, which are color-coded according to the value of the video data n, that is, the signal strength, and the area where the signal exists. color image
This means that it can be displayed on the RGB color display 121. Note that by converting this RGB drive signal r and further mixing it with a synchronization signal to produce a so-called NTSC standard color video signal, the color video can be displayed on a display television. As described above, according to the present invention, radar video signals can be displayed in real time as high-brightness color images with desired colors based on differences in signal strength in designated areas. Not only can it be observed by many observers at the same time in daylight, but also images of targets in noise, which were previously difficult to distinguish, are now displayed in different colors. This made it extremely easy to identify. Furthermore, areas that require special attention can be colored and displayed using a special color scheme, making it easier to quickly identify targets in dangerous areas and make decisions. . Further, according to the present invention, by changing the coordinate transformation method from the conventional multiplication method to an addition method using an accumulator, calculations are simplified, and the calculation time can be increased and the cost of the device can be reduced. In addition, the increase in errors caused by repeating the accumulation many times, which is considered a drawback, can be avoided by increasing the number of digits in calculations, and even considering this increase in the number of digits, the calculation time due to the complex calculations of the multiplication method is It has significant advantages compared to its low speed and high price. In particular, in the case of video display using signals received from radar or the like, the time allowed for coordinate transformation is generally small, so high-speed calculation is required, and this method has great advantages. Next, the present invention provides an access number controller that can control the number of accesses to the video memory in order to correct the unevenness of video information density that occurs between the center and the periphery when converting from polar coordinates to rectangular coordinates. By providing this, it is possible to display homogenized video information over the entire screen.
Furthermore, in the present invention, the information stored in the video memory is not only current information, but also allows execution of a large width priority write method so that current information can be superimposed and stored in addition to past information. Therefore, the track of a moving target can also be displayed, making it possible to determine its moving speed and course trend.

[Brief explanation of the drawing]

FIG. 1 is a block diagram 2 showing an embodiment in which the display device according to the present invention is used in a radar transceiver.
The figure is a block configuration diagram showing one embodiment of the present invention, FIG. 3 is an explanatory diagram of each operation based on the block configuration of FIG. 2, FIG.
The figure is an explanatory diagram of the scanning pattern on a cathode ray tube.
The figure is a configuration diagram of a video memory. 101...Quantizer, 102A, 102B...
Buffer memory, 103... Integrator, 104...
Extraction memory, 106...Access number controller, 1
09...Digital resolver, 110...Accumulator,
111...Video memory, 116...Large amplitude priority circuit, 117...Color code converter, 301...
Memory controller, 302...Dynamic random access memory chip, 303...Data selector, 304...Serial to parallel converter, 121...
RGB color display, 123...Area specification memory.

Claims (1)

[Scope of Claims] 1. Periodic video signals at polar coordinate positions obtained by periodically transmitting pulsed energy from a transmitter and receiving the reflected signals as the video signals at corresponding orthogonal coordinate positions, and A display device that displays a desired color, comprising: a quantizer that sequentially quantizes the video signal at one or more sampling rates to obtain a digital video signal having color information; and an output of the quantizer. An integrator that periodically integrates a quantized video signal, which is a signal, and one of the quantizer or the output of the integrator is input, and this input signal is temporarily stored, and the period of the transmission trigger of the transmitter or the output of the integrator is input. a video processing unit comprising an extraction memory capable of extracting the quantized video signal in synchronization with a period that is an integral multiple; and a converter that converts the sine and cosine values into digital quantities, and the sine and cosine values obtained from the converter are cumulatively added together using a control signal corresponding to a fixed sampling unit distance, and then divided into fixed angles and fixed distances and sampled. a coordinate conversion section comprising an accumulator capable of converting each sampled polar coordinate position into a corresponding sampled orthogonal coordinate position; and an image having one screen of color information using the output signal from the extraction memory as input. a video memory capable of storing a signal at a corresponding orthogonal coordinate position transformed by the coordinate conversion section; and an area designation for storing information for dividing a video memory area storing the video signal having the color information into a plurality of arbitrary regions. a color code converter that inputs a video signal having color information to be read from the video memory and a region discrimination signal read from the region designation memory and outputs a desired color video signal in accordance with the combination thereof; , reading out a video signal having color information stored in the video memory in synchronization with the television scanning speed and an area discrimination signal corresponding to the position of the video signal, and obtaining a desired colored video signal obtained from these two signals; , the output signal from the extraction memory is compared with the signal read from the corresponding address to be written in the video memory, and the signal with the greater signal strength is selected. and large signal priority means for rewriting the image into the video memory. 2 Periodic video signals at polar coordinate positions obtained by periodically transmitting pulsed energy from a transmitter and receiving the reflected signals are used as the video signals at corresponding orthogonal coordinate positions, and have desired colors. A display device for displaying a display, comprising: a quantizer that sequentially quantizes the video signal at one or more sampling rates to obtain a digital video signal having color information; and a quantized video signal that is an output signal of the quantizer. An integrator that periodically integrates a signal and either the quantizer or the output of the integrator are input, and this input signal is temporarily stored and synchronized with the transmission trigger period of the transmitter or an integral multiple period. a video processing unit comprising an extraction memory capable of extracting the quantized video signal by converting the quantized video signal into sine and cosine digital quantities; The sine and cosine values obtained from the transducer and the transducer are cumulatively added together using a control signal corresponding to a fixed sample unit distance, and polar coordinate positions divided and sampled at fixed angles and fixed distances are respectively calculated. a coordinate conversion unit comprising an accumulator capable of converting to a corresponding sampled orthogonal coordinate position; and a coordinate conversion unit that inputs the output signal from the extraction memory and converts the video signal having color information of one screen into the coordinate conversion unit. a video memory that can be stored at a corresponding orthogonal coordinate position converted by; an area designation memory that stores information for dividing a video memory area that stores the video signal having the color information into arbitrary plural areas; and the video memory. a color code converter that inputs a video signal having color information read from the area designation memory and an area discrimination signal read from the area designation memory and outputs a desired color video signal in accordance with the combination; Then, a video signal having color information stored in the video memory and an area discrimination signal corresponding to the position of the video signal are read out, and orthogonal display is performed using a desired colored video signal obtained from these two signals. an orthogonal coordinate system display means, which compares the output signal from the extraction memory and the signal read from the corresponding address to be written in the video memory, selects the signal with the greater signal strength, and displays the signal in the video memory; and access frequency control means for generating a control signal for permitting or prohibiting writing of color information to the video memory according to the sampled angle and distance of the polar coordinates. A display device characterized by: