Display system, visibility evaluation method, and method of determining size of visual target

Patent metadata

Field	Value
Publication number	US-2020355917-A1
Application number	US-202016869254-A
Country	US
Kind code	A1
Filing date	May 7, 2020
Priority date	May 7, 2019
Publication date	Nov 12, 2020
Grant date	—

Abstract

The display system includes a first storage unit storing standardized data composed chromaticity values and luminance values. An information acquirer acquires luminance values and chromaticity values of a visual target and luminance and chromaticity values of a background thereof. A standardization unit standardizes the chromaticity values and the luminance values of the visual target and the background based on these chromaticity values and the luminance values of the visual target and the background thereof and the standardized data stored in the first storage unit. A visual target contrast calculator calculates a contrast of a visual target to a background by measuring a distance in a color space between the visual target and the background each defined by the standardized luminance and chromaticity values. A second storage unit stores an expression defining a relation between the contrast thereof to the background and a size of the visual target.

First claim

What is claimed is:

1 . A display system for displaying a visual target, comprising:
a first storage unit to store standardized data composed of chromaticity values and luminance values; an information acquirer to acquire luminance values and chromaticity values of the visual target and a luminance value and a chromaticity value of a background of the visual target; a standardization unit to standardize the chromaticity values and the luminance values of the visual target and the background of the visual target acquired by the information acquirer based on the standardized data stored in the first storage unit and the chromaticity values and the luminance values of the visual target and the background of the visual target acquired by the information acquirer; a visual target contrast calculator to calculate a contrast of a visual target to a background by measuring a distance in a color space between the visual target defined by the standardized luminance and chromaticity values and the background defined by the standardized luminance and chromaticity values; a second storage unit to store an expression defining a relation between a contrast of a visual target to a background and a size of a visual target; and a size determiner to determine a size of the visual target by substituting the contrast of the visual target to the background, calculated by the visual target contrast calculator into the expression.

2 . The display system as claimed in claim 1 , wherein the first storage unit stores multiple combinations of standardized data generated by the standardization unit by repeatedly standardizing luminance values and corresponding chromaticity values of the visual target and the background of the visual target,
each of the multiple combinations of standardized data being composed of a luminance value and a corresponding chromaticity value of the visual target and a luminance value and a corresponding chromaticity value of the background of the visual target, wherein the expression is a first approximate expression established based on multiple contrasts of the visual target to the background and multiple sizes of the visual target corresponding to the contrasts, respectively.

3 . The display system as claimed in claim 2 , further comprising:
an approximate expression calculator to establish a second approximate expression based on the multiple combinations of standardized data composed of luminance values and corresponding chromaticity values and sizes of the visual target corresponding to the multiple combinations of standardized data, and an approximate expression selector to select one of the first and second approximate expressions having a higher determination coefficient, the determination coefficient indicating a matching rate at which a size of a visual target and a contrast of a visual target to a background collectively meet corresponding one of the first and second approximate expressions, wherein the size determiner uses one of the first and second approximate expressions selected by the approximate expression selector to determine the size of the visual target.

4 . The display system as claimed in claim 1 , wherein the display system constitutes a head-up display.

5 . A visibility evaluation method comprising the steps of:
acquiring multiple luminance values and chromaticity values of a visibility evaluation target and luminance and chromaticity values of a background of the visibility evaluation target; standardizing the acquired luminance values and chromaticity values of the visibility evaluation target and the background thereof based on the acquired luminance values and chromaticity values of the visibility evaluation target and the background thereof and previously standardized and stored luminance values and chromaticity values; and calculating a distance in a color space between the visibility evaluation target defined by the standardized luminance and chromaticity values and the background thereof defined by the standardized luminance and chromaticity values.

6 . A size determination method for determining a size of a visual target displayed in a display system, comprising the steps of:
acquiring multiple luminance values and chromaticity values of a visibility evaluation target and luminance and chromaticity values of a background of the visibility evaluation target; standardizing the acquired luminance values and chromaticity values of the evaluation target and the background thereof based on the acquired luminance values and chromaticity values of the evaluation target and the background thereof and previously standardized and stored luminance values and chromaticity values; calculating a contrast of a visual target to a background by measuring a distance in a color space between the visibility evaluation target defined by the standardized luminance and chromaticity values and the background thereof defined by the standardized luminance and chromaticity values; and determining a size of the visual target by substituting the contrast of the visual target to the background, calculated in the step of calculating the distance into an expression defining a relation between the size of the visual target and the contrast of the visual target to the background.

7 . A display system for displaying a visual target, comprising:
an information acquirer to acquire background information indicating at least one of a luminance value and a chromaticity value of a background of the visual target; and a display size determiner to determine a size of the visual target based on evaluation of visibility of the visual target relative to the background, the evaluation of visibility being performed based on a standard display size of the visual target and the background information.

Assignees

• Denso Corp
• The Kitasato Inst

Inventors

• Ogawa Hiroaki
• Enya Takeshi
• Kawamorita Takushi

Classifications

• G02B2027/0116

  comprising devices for correcting chromatic aberration · CPC title

• G02B2027/014

  comprising information/image processing systems · CPC title

• G02B2027/0118

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

• G02B27/0101 Primary

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

• G02B2027/0138

  comprising image capture systems, e.g. camera · CPC title