JPS5975767A - Evaluating method of hue and color saturation of television receiver - Google Patents

Abstract

PURPOSE:To evaluate the color saturation and hue of a receiver easily by connecting a signal generator to a receiver, and measuring specific screen data generated by adjusting the generator through an optical filter. CONSTITUTION:A figure shows a video waveform on a screen A-A'. The waveform has a color signal 5 in an R primary color pattern 2. A color television receiver which has specific color separation is set by using an unshown signal generator so that a luminance signal 4 and an R primary color signal 5 has the same level at a pattern part 1. Consequently, the luminance of a luminance pattern part 1 becomes equal to that of an R fluorescent material at the R primary color signal pattern part 2 and when measurements are taken through an optical filter of R, it is found that both pattern parts 1 and 2 have the same luminance. The R primary color signal 5 varies in color amplitude with the color saturation of the color television receiver, so screen pattern parts 1 and 2 are compared with each other to evaluate the color saturation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a method for evaluating the reproducibility of hue and color saturation, which are one of the factors in determining whether the image quality of a color television receiver is good or bad.

[Prior art]

The conventional evaluation method for hue and color saturation in color television receivers uses a color par signal generator with red, green, and blue primary color signals, and after displaying the color par, the color demodulation circuit of the color television receiver In the latter stage, with a vector scope,
Rather than measuring the phases of R, G, and H, evaluate the hue.
Also, in the latter stage of the color demodulation circuit, a synchroscope TR,
Since this method evaluated color saturation by measuring the G and B amplitudes, it had the disadvantage that it was necessary to connect the measuring device to the circuit of the color television receiver, and it took time to connect. Ta. Furthermore, since the evaluation using a color television screen was a sensory evaluation, there was a drawback that accurate evaluation could not be made.

[Purpose of the invention]

The present invention has been made in order to eliminate the drawbacks of the prior art as mentioned above, and it is therefore an object of the present invention to eliminate the need for connecting a measuring instrument to the receiver circuit, and to eliminate the need for sensory evaluation. An object of the present invention is to provide a method for evaluating the hue and color saturation of a television receiver, which can be accurately evaluated in a simple manner without depending on the situation.

[Summary of the invention]

In the present invention, the color saturation of the R monochromatic signal can be measured by measuring the R color signal of a color television screen through an R optical filter.

This measurement value is the demodulation axis of color television (R-Y)
On the axis, it is a value obtained by adding the color amplitude value on the (RY) axis and the luminance amplitude value of R. Furthermore, by similarly measuring the luminance signal, the luminance amplitude value of R can be measured. Therefore, by setting the color amplitude using the signal generator so that the above two measured values are equal at a predetermined color saturation, it becomes possible to evaluate the color saturation from the difference between the measured values. On the other hand, a color signal whose demodulation axis has a phase of 90° with respect to the (R-Y) axis has no color amplitude component on the (R-Y) axis, and this signal pattern is measured through an R optical filter. Then, only the luminance component can be measured. Therefore, by measuring a pattern obtained by multiplexing a predetermined luminance signal component on the corresponding color signal and a luminance signal pattern of the same level through an R optical filter, it is possible to If the phase is 90', the two measured values will be equal, and if there is a phase shift, a difference will occur in the measured values. Therefore, the hue can be evaluated by comparing the measured values.

The above has been an explanation of the R color signal, but the G signal, B
A similar principle holds true for signals.

[Embodiments of the invention]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is an explanatory diagram of a pattern displayed by a signal generator on the screen of a television receiver in order to implement the present invention. In the figure, the pattern consists of a 1°2.3 area, where 1 is the luminance signal, 2 is the R primary color signal, and 3 is 90° for H.
This is a display pattern of a color signal with a phase of °.

FIG. 2 shows the entire video waveform of screen A-A'+ in FIG. The color signal 5 is included in the R primary color signal pattern 20 portion. In a color television receiver having a predetermined color saturation, a signal generator (not shown) is used to set the luminance signal 4 and the R primary color signal 5 in the pattern portion 1 to be at the same level. As a result, the brightness of the brightness signal pattern portion 1 and the brightness of the R phosphor of the R primary color signal pattern portion 2 can be measured through the same optical filters. 2 can be measured as the same brightness. Since the color amplitude of the R primary color signal 5 changes depending on the strength of the color saturation of a color television receiver, the color saturation can be evaluated by comparing the one-screen pattern portions 1 and 2.

FIG. 3 is a video waveform for screen BB' in FIG. The pattern portion 3 includes the color signal 6, and the brightness signal levels of the brightness signal 4 and the color signal 6 in the pattern portion 1 are equal.

FIG. 4 shows the phase of each color signal with respect to the color demodulation axis. The figure shows an R primary color signal 5 and a color signal 6 having a 90' phase. By measuring the screen displaying color signals 5 and 6 through the R filter, each color signal is determined as (R-Y
) The projected amplitude value on axis 1 is measured. The phase of the color signal is rotated by a signal generator (not shown), and the color signal 6 is converted to (R
By setting the color amplitude of the color signal 6 to have a phase difference of 90° with respect to the (R-Y) axis, the color amplitude of the color signal 6 does not appear on the (R-Y) axis, but is By measuring, the pattern part 3 containing the signal pattern part 1 and the color signal 6 can be measured as having the same luminance as (ri).

Since the amplitude of the color signal 6 on the (RY) axis changes depending on the hue of the color television, the hue can be evaluated by comparing the pattern portions 1 and 3.

FIG. 5 is a perspective view showing the arrangement of instruments used in carrying out the invention. In the figure, 9 is a color television receiver, 1
0 indicates a signal generator, and 11 indicates an optical filter.

Connect a color television receiver 9Vc signal generator 10, adjust the signal generator 10 to generate a predetermined pattern on the screen 1c of the receiver 9, and measure it through an optical filter 11. This makes it possible to read and evaluate the results.

〔Effect of the invention〕

According to the present invention, a signal generator is connected to a color television receiver, and a predetermined screen generated by adjusting the generator is measured through an optical filter. Since the color saturation and hue of a television receiver can be evaluated, there is no need to connect a measuring device to the television circuit and read the measured values as in the past, and there is an advantage that the evaluation can be easily performed.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a pattern displayed on the screen of a television receiver to implement the present invention, and FIG. 2 is a waveform diagram showing a video signal waveform for screen A-A' in FIG. 1. 3 is a waveform diagram showing the video signal waveform for the screen B-B' in FIG. FIG. 2 is a perspective view showing the arrangement of instruments in practice. Description of symbols 1... Luminance signal section, 2... R primary color signal section, 3...
A color signal section having a phase of 90° with respect to the R primary color signal, 4.
...Video waveform of luminance signal section 1, 5...Video waveform of R primary color signal section 2, 6...Video waveform of color signal section 5, 9
...Color television receiver, 10...Signal generator, 1
1...Optical filter. Representative Patent Attorney Susuki 1) Yukio Toshi / Nissai 4 Teno 5 (2)

Claims (1)

[Claims] 1) A first screen pattern that displays a luminance signal, a second screen pattern that displays an arbitrary primary color signal having a predetermined color amplitude, and a color signal that has a phase difference of 90° with respect to the primary color signal. A third screen pattern is simultaneously displayed on the same screen of a television receiver using a signal generator, and the luminance signal component in the first screen pattern and the luminance signal component in the third screen pattern are the same. After adjusting the signal generator so that the first screen pattern and the third screen pattern are displayed on the screen of the receiver through an optical filter,
Evaluate the quality of the hue reproducibility of the receiver by looking at the screen pattern to see if both screens have the same brightness. After being evaluated as good, the first screen pattern and the second screen pattern displayed on the screen of the receiver are viewed, and the color saturation of the receiver is determined depending on whether the brightness of both screens is equal or not. 1. A method for evaluating hue and color saturation of a television receiver, characterized in that the quality of color reproducibility is evaluated.