JPS6320680U

JPS6320680U -

Info

Publication number: JPS6320680U
Application number: JP11430586U
Authority: JP
Priority date: 1986-07-25
Filing date: 1986-07-25
Publication date: 1988-02-10

Description

[Brief explanation of the drawing]

第１図、第２図はそれぞれこの考案の実施例に
おける受光素子の配置状態の例を示す斜視図、第
３図は視覚表示装置の陰極線管の一例の構造を示
す説明図、第４図は陰極線管の前面パネルガラス
を出入する光の種類を示す説明図、第５図は第４
図に示す光の輝度の関係を示す説明図、第６図は
像の鮮明さと外部の光の輝度の関係を示すグラフ
図、第７図は従来の視覚表示装置の外部調節ダイ
ヤルの設置状態を示す斜視図である。図において３は前面パネルガラス、５は外部調
節ダイヤル、６は受光素子である。尚、各図中同
一符号は同一又は相当部分を示す。 1 and 2 are perspective views showing an example of the arrangement of light receiving elements in an embodiment of this invention, FIG. 3 is an explanatory view showing the structure of an example of a cathode ray tube of a visual display device, and FIG. An explanatory diagram showing the types of light entering and exiting the front panel glass of a cathode ray tube.
Fig. 6 is a graph showing the relationship between the sharpness of the image and the brightness of external light, and Fig. 7 shows the installation state of the external adjustment dial of a conventional visual display device. FIG. In the figure, 3 is a front panel glass, 5 is an external adjustment dial, and 6 is a light receiving element. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims

[Scope of utility model registration request]

In a visual display device whose display portion is a cathode ray tube, a light receiving element is arranged around the front panel glass of the cathode ray tube to sense the intensity of external light around the cathode ray tube and convert it into an electrical signal, and an electronic an external adjustment dial that controls the beam and adjusts the brightness of the light emitted when the electron beam collides with the fluorescent screen; a drive motor connected to the external adjustment dial that drives its angular position; and the output of the light receiving element. From the signal, external light is reflected by the fluorescent screen on the inside surface of the front panel glass of the cathode ray tube, and the brightness of the reflected light emitted to the outside of the front panel glass is calculated, and an electron beam is applied to the fluorescent screen of the cathode ray tube. The angular position of the external adjustment dial that makes the ratio of the brightness of the transmitted light transmitted through the front panel glass and the brightness of the reflected light to a predetermined constant value is output as a reference angular position. A visual display device comprising: an arithmetic element; and means for driving the drive motor by the output of the arithmetic element so that the angular position of the external adjustment dial matches the reference angular position.