Index calculation apparatus and display system

Patent metadata

Field	Value
Publication number	US-11281001-B2
Application number	US-202016808728-A
Country	US
Kind code	B2
Filing date	Mar 4, 2020
Priority date	Mar 6, 2019
Publication date	Mar 22, 2022
Grant date	Mar 22, 2022

Abstract

An index calculation apparatus is provided with a luminance acquiring unit, a chromaticity acquiring unit and an index calculation unit. The luminance acquiring unit is configured to acquire a luminance Y of an evaluation object of visibility. The chromaticity acquiring unit is configured to acquire a chromaticity U of the evaluation object. The index calculation unit is configured to calculate an index V expressed by following equation by using the luminance Y and the chromaticity U·V=KYU . . . (1), where K is a constant.

First claim

What is claimed is:

1. An index calculation apparatus comprising:
a luminance acquiring unit configured to acquire a luminance Y of an evaluation object of visibility;
a chromaticity acquiring unit configured to acquire a chromaticity U of the evaluation object; and
an index calculation unit configured to calculate an index V expressed by following equation by using the luminance Y and the chromaticity U,
V=KYU   (1),

where K is a constant.

2. An index calculation apparatus comprising:
a first luminance acquiring unit configured to acquire a first luminance Y 1 which is a luminance of a visual object displayed by a display apparatus;
a first chromaticity acquiring unit configured to acquire a first chromaticity U 1 which is a chromaticity of the visual object;
a second luminance acquiring unit configured to acquire a second luminance Y 2 which is a luminance of a background of the visual object;
a second chromaticity acquiring unit configured to acquire a second chromaticity U 2 which is a chromaticity of the background; and
an index contrast calculation unit configured to calculate an index contrast C expressed by following equation (2) by using the first luminance Y 1 , the second luminance Y 2 , the first chromaticity U 1 and the second chromaticity U 2 ,
C=K ( Y 1 U 1− Y 2 U 2)  (2),

where K is a constant.

3. An index calculation apparatus comprising:
a first luminance acquiring unit configured to acquire a first luminance Y 1 which is a luminance of a visual object displayed by a display apparatus;
a first chromaticity acquiring unit configured to acquire a first chromaticity U 1 which is a chromaticity of the visual object;
a second luminance acquiring unit configured to acquire a second luminance Y 2 which is a luminance of a background of the visual object;
a second chromaticity acquiring unit configured to acquire a second chromaticity U 2 which is a chromaticity of the background; and
an index contrast calculation unit configured to calculate an index contrast C expressed by following equation or an inverse of the index contrast C by using the first luminance Y 1 , the second luminance Y 2 , the first chromaticity U 1 and the second chromaticity U 2 ,
C =( Y 1 U 1)/( Y 2 U 2)  (3).

4. An index calculation apparatus comprising:
a first luminance acquiring unit configured to acquire a first luminance Y 1 which is a luminance of a visual object displayed by a display apparatus;
a first chromaticity acquiring unit configured to acquire a first chromaticity U 1 which is a chromaticity of the visual object;
a second luminance acquiring unit configured to acquire a second luminance Y 2 which is a luminance of a background of the visual object;
a second chromaticity acquiring unit configured to acquire a second chromaticity U 2 which is a chromaticity of the background; and
an index contrast calculation unit configured to calculate an index contrast C expressed by following equation or an inverse of the index contrast C by using the first luminance Y 1 , the second luminance Y 2 , the first chromaticity U 1 and the second chromaticity U 2 ,
C =[( Y 1 U 1)−( Y 2 U 2)]/[( Y 1 U 1)+( Y 2 U 2)]  (4).

5. A display system comprising:
a display apparatus; and
an index calculation apparatus including:
a first luminance acquiring unit configured to acquire a first luminance Y 1 which is a luminance of a visual object displayed by a display apparatus;
a first chromaticity acquiring unit configured to acquire a first chromaticity U 1 which is a chromaticity of the visual object;
a second luminance acquiring unit configured to acquire a second luminance Y 2 which is a luminance of a background of the visual object;
a second chromaticity acquiring unit configured to acquire a second chromaticity U 2 which is a chromaticity of the background; and
an index contrast calculation unit configured to calculate an index contrast C expressed by following equation or an inverse of the index contrast C by using the first luminance Y 1 , the second luminance Y 2 , the first chromaticity U 1 and the second chromaticity U 2 ,
C =[( Y 1 U 1)−( Y 2 U 2)]/[( Y 1 U 1)+( Y 2 U 2)]  (4),

wherein
the display apparatus is configured to display characters as the visual object; and
the display apparatus includes a size calculation unit configured to calculate a size of the characters depending on the index contrast C.

6. The display system according to claim 5 , wherein
the display apparatus is provided with a plurality of light sources producing different colors of light; and
the display apparatus is configured to mix the light of the plurality of light sources, thereby displaying the visual object.

Assignees

• Denso Corp

Inventors

• Ogawa Hiroaki
• Enya Takeshi

Classifications

• G06F17/11

  for solving equations {, e.g. nonlinear equations, general mathematical optimization problems (optimization specially adapted for a specific administrative, business or logistic context G06Q10/04)} · CPC title

• G06V20/56

  exterior to a vehicle by using sensors mounted on the vehicle · CPC title

• G02B2027/0116

  comprising devices for correcting chromatic aberration · CPC title

• G02B27/0101 Primary

  characterised by optical features (G02B27/0172 takes precedence) · CPC title

• G02B2027/0118

  comprising devices for improving the contrast of the display / brillance control visibility · CPC title