JPS63250544A - Brightness evaluation device for lighting equipment appearing on crt - Google Patents

Abstract

PURPOSE:To evaluate lighting equipment properly by calculating the permissible limit value of the brightness of the lighting equipment appearing on a CRT from the value of the specular surface reflection factor and perpendicular surface illuminance of the CRT and also measuring and comparing the brightness with the permissible limit value. CONSTITUTION:This evaluation device consists of, for example, a specular surface illuminance decision part 3, brightness permissible limit value arithmetic parts 4-7, a brightness measurement part 8, a decision part 9, etc. Further, the arithmetic parts 4-7 calculate the brightness permissible limit values according to the perpendicular surface illuminance of the CRT. Then the value of the specular surface reflection factor of the CRT is inputted to an input part 1 and the value of the perpendicular surface illuminance is inputted to an input part 2; and the decision par 3 sends a signal to the arithmetic parts 4-7 corresponding to the perpendicular surface illuminance to output the brightness permissible limit value of the lighting equipment. Then the value of the brightness on the CRT which is measured by the measurement 8 is compared with the brightness permissible limit value and the result is displayed on a display part 10. Consequently, whether or not the lighting equipment is proper is easily evaluated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is applicable to lighting equipment used in a VDT working environment.
This relates to an evaluator that has the function of determining whether the lighting equipment is appropriate in terms of how the characters displayed on the CRT screen appear.

Automation of office work is progressing rapidly with the introduction of conventional technology OA type equipment. As a result, workers who use VDTs, which are the mainstay of OA equipment, have complained of eye strain and stiff shoulders. ``Lighting Research and Investigation Committee''
The lighting standards for VDT work have been established in Among these, in VDT work environments, it is recommended to use lighting equipment whose brightness in the area with a cutoff angle of 60 degrees or more is regulated to 200 cd/++2 or less (1111 degree tolerance limit value is 200 cd/m2). There is. Brightness tolerance limit value 20
00d/m2 is CR without anti-reflection treatment on the surface.
It is defined for T.

After that, in addition to the conventional non-surface treatment, CRT surface treatment techniques were put into practical use, such as applying a matte treatment using a method that imparts scattering properties to the CR7 surface, and applying a multilayer thin film coating. CI'tTs with anti-reflection treatment are on the rise. C like this
Since the value of specular reflectance for FLT is smaller than that of CRT whose surface is not subjected to anti-reflection treatment, the permissible brightness limit of 200 cd/m2 for lighting equipment cannot be applied.

Problems to be Solved by the Invention As described above, the allowable luminance limit value of a lighting fixture for a CRT with a low specular reflectance that has been subjected to an anti-reflection treatment on its surface is different from that of a conventional CRT that has an anti-reflection treatment on its surface and has a low specular reflectance. Brightness tolerance limit value 200 determined for CI'tT with high rate
Unlike cd/+n2, it should be a value larger than 200cd/+n2, but there is no fixed value yet. Therefore, it was not possible to evaluate whether the lighting equipment in use was suitable for CRTs whose surfaces were subjected to anti-reflection treatment in terms of how the displayed characters looked.

The present invention has been made in view of the above points, and has a simple configuration to determine the permissible brightness limit value of a lighting fixture adapted to CFLT having an arbitrary specular reflectance value from the viewpoint of visibility of display characters, and to use the method. An object of the present invention is to provide a luminance evaluator for a luminaire that determines whether the luminance value of the luminaire is acceptable when the luminaire is reflected on a CRT.

Means for Solving the Problems In order to solve the above problems, the present invention uses the permissible brightness limit of 200 cd/m2 for lighting equipment for CRTs whose surfaces have not been subjected to anti-reflection treatment as a standard. We clarified the relationship between the specular reflectance of a CRT and the luminance of a lighting fixture under the condition that the value is equal to the noise level. in general,
The noise level of the reflected image of the lighting equipment on the CRT screen corresponds to the subjective evaluation of the legibility of the displayed characters on the CRT, and it is thought that if the noise level values are the same, the degree of legibility of the displayed characters will be the same. It will be done. Noise level (NL
) is expressed as follows.

NL=C/Cm1n where C= LoX Rs/(4,9X10-2X Ev)
Cmin=0.05936X[(1,639/(4,9
X102×Ev))0・4+1]2・5 LO: Luminance of lighting equipment [cd/m2] Rs: Specular reflectance of CRT EV: Vertical illuminance of CRT [1x] Therefore, the brightness evaluator of the present invention is a CRT Using the characteristics of the specular reflectance and luminance of the lighting fixture, find the luminance tolerance limit value of the lighting fixture for a CRT with an arbitrary specular reflectance value, and calculate this value and the luminance value of the 11a bright fixture used. The purpose of this test is to compare the relationship between the magnitude of the luminance and evaluate whether the luminance value of the lighting equipment is acceptable in terms of the visibility of displayed characters based on the noise level when the lighting equipment is reflected on a CRT. .

Effect The present invention uses the above-described configuration to measure the brightness of the lighting equipment reflected on the CRT surface, and calculate the value of the specular reflectance of the CRT and the CR.
Input the value of the vertical illuminance of T, and calculate the permissible brightness limit value of the lighting fixture adapted to CI'tT from the characteristics of the specular reflectance of the CRT and the brightness of the lighting fixture, which are obtained under the condition that the noise level value is constant. By determining the value and comparing the magnitude relationship with the luminance value of the II(f closed fixture), it is possible to evaluate whether the lighting fixture is adapted to C1''tT.

Embodiment FIG. 1 is a block diagram showing an embodiment of a luminance evaluator for a lighting fixture reflected on a CRT according to the present invention.

In FIG. 1, 1 is a specular reflectance input section, 2 is a vertical illuminance input section, 3 is a vertical illuminance determination section, 4 to 7 are calculation sections for brightness allowable limit values, 8 is a brightness measurement section, and 9 is a brightness measurement section. The determination section 10 is a display section.

Figures 2 to 5 show brightness allowable limit value calculation units 4 to 7, respectively.
FIG. These figures are based on the noise level when a 200 cd/m2 lighting fixture is reflected on a CRT whose surface has not been subjected to anti-reflection treatment, and are based on several representative existing CRTs with different anti-reflection treatment on the surface. The characteristics of the specular reflectance of the CRT and the brightness of the lighting fixture are obtained by measuring the specular reflectance of the CItT, and based on these measurement data, under the condition that the noise level value is equal to the reference value.

When the vertical illuminance of the CRT is 2001x or less, the permissible brightness limit value is calculated in the brightness permissible limit calculation unit 4 having the characteristics shown in FIG.
If the vertical illuminance of the CRT is larger than 1x and 3001x or less, the brightness allowable limit calculation unit 5 having the characteristics shown in FIG. In the value calculation unit 6, C
The vertical illumination of RT is greater than 4001x.
If the value is less than or equal to x, the permissible brightness limit value is calculated in the permissible brightness limit calculation unit 7 having the characteristics shown in FIG.

The operation of the brightness evaluator for the lighting equipment reflected on the CRT according to the present embodiment configured as described above will be explained below with reference to FIGS. 1 and 3.

1,9X10- whose specular reflectance value corresponds to A in Figure 3
2, 1300 on the CRT whose surface has been treated with a matte finish.
Suppose that a cd/m2 lighting fixture is reflected. It is assumed that the vertical illuminance of the CRT at this time is 300]x.

In the specular reflectance input section 1, the specular reflectance value of the CRT is 1.9.
Input X10-2. The vertical illuminance value 3001x of the CRT is input to the vertical illuminance input section 2. The vertical illuminance determination section 3 determines the signal output from the vertical illuminance input section 2 and outputs the signal to the luminance permissible limit value calculation section 5 . The luminance permissible limit value calculating section 5 calculates the luminance permissible limit value of 920 cd/m'' for the lighting equipment from the signal output from the specular reflectance input section 1 according to the characteristics shown in FIG. 3, and outputs a signal corresponding to that value. do.

The brightness measuring section 8 measures the brightness of the lighting fixture reflected on the CRT and outputs a signal corresponding to the brightness value of 1300 ed/m2. Brightness allowable limit value calculation unit 5 and brightness measurement unit 8
The signal output from 0 is input to the determination unit 9.
determines the magnitude relationship between the brightness allowable limit value and the measured brightness value, and if the brightness allowable limit value is greater than the measured brightness value, an appropriate signal is output, and the brightness allowable limit value is smaller than the measured brightness value. If the display unit 10 outputs an inappropriate signal, the display unit 10 outputs a display corresponding to the appropriate signal or the inappropriate signal output from the determination unit 9.
cd/m2 is smaller than the measured luminance value of 1300 cd/m2, an inappropriate signal is output, and the display unit 10 displays a display corresponding to the inappropriate signal. Therefore, the specular reflectance value is 1.9X10-2. It can be seen that a lighting fixture with a luminance of 1300 cd/m2 is inappropriate for a CRT whose surface has been subjected to a matte treatment, in terms of how the displayed characters appear based on the noise level.

Effects of the Invention As described above, according to the present invention, the brightness tolerance of a lighting fixture adapted to a CRT having an arbitrary specular reflectance value can be improved with a simple configuration from the viewpoint of the appearance of displayed characters based on the noise level. By determining the limit value and comparing the magnitude relationship between that value and the luminance value of the lighting equipment being used, it is possible to evaluate whether the lighting equipment is appropriate, which is extremely useful in practice.

[Brief explanation of drawings]

Fig. 1 is a block diagram of a luminance evaluator for a lighting fixture reflected on a CRT according to an embodiment of the present invention, Fig. 2 is a characteristic diagram of the luminance permissible limit value calculation section of the evaluator, and Fig. 3 is a diagram of the luminance permissible limit value calculation section of the evaluator. FIG. 4 is a characteristic diagram of the limit value calculation section, FIG. 4 is a characteristic diagram of the brightness allowable limit value calculation section, and FIG. 5 is a characteristic diagram of the brightness allowable limit value calculation section. DESCRIPTION OF SYMBOLS 1... Specular reflectance input part, 2... Vertical illuminance input part, 3... Vertical illuminance judgment part, 4-7... Brightness tolerance limit value calculation part, 8... Brightness measurement part , 9... Judgment section, 1
0...Name of display department agent Patent attorney Toshio Nakao 1 person Figure 2 CRT's *11rINM rod Figure 3 CRT's specular reflection Figure 4 CRT's mirror reflection

Claims (1)

[Claims] a specular reflectance input section for inputting the value of the specular reflectance of the CRT; a vertical illuminance input section for inputting the value of the illuminance of the vertical plane of the CRT; a determination section for determining the vertical illuminance of the CRT; a calculation unit that calculates the permissible limit value of the brightness of the lighting equipment reflected on the CRT from the value of the ratio and the vertical illuminance;
comprising a brightness measurement unit that measures the brightness of the lighting equipment reflected in the image, a determination unit that compares and determines the magnitude relationship between the brightness allowable limit value and the measured brightness value, and a display unit that displays the determination result. A luminance evaluator for lighting equipment reflected on a CRT.