JPS5630677A - Automatic luminance regulator - Google Patents
Automatic luminance regulatorInfo
- Publication number
- JPS5630677A JPS5630677A JP10703279A JP10703279A JPS5630677A JP S5630677 A JPS5630677 A JP S5630677A JP 10703279 A JP10703279 A JP 10703279A JP 10703279 A JP10703279 A JP 10703279A JP S5630677 A JPS5630677 A JP S5630677A
- Authority
- JP
- Japan
- Prior art keywords
- luminance
- transistor
- display tube
- power source
- fluorescent display
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Electric Clocks (AREA)
- Indicating Measured Values (AREA)
- Control Of Indicators Other Than Cathode Ray Tubes (AREA)
Abstract
PURPOSE: To vary the luminance of a display tube according to a ambient brightness with a simple construction by applying voltage between the collector and the emitter of a luminance reglating transistor to the base thereof after it is divided with a photo detector and a resistance.
CONSTITUTION: Transistors Q1 and Q2 for regulating luminance are connected in parallel between a filament F of a fluorescent display tube FL and one end of a smoothing capacitor C1 of a DC power source obtained by rectifying the commertial power source. A transistor Q3 switches on by a frequency of the commertial power source at a specified duty cycle to secure the minimum luminance of the fluorescent display tube FL. A voltage obtained dividing the voltage between the collector and the emitter of the transistor Q1 with a photo detector R3 and a resistance R4 is applied to the base of the tansistor to vary the level of energization of the transistor Q1 whereby the luminance of the fluorescent display tube is automatically changed according to the ambient brightness.
COPYRIGHT: (C)1981,JPO&Japio
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP10703279A JPS5630677A (en) | 1979-08-22 | 1979-08-22 | Automatic luminance regulator |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP10703279A JPS5630677A (en) | 1979-08-22 | 1979-08-22 | Automatic luminance regulator |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS5630677A true JPS5630677A (en) | 1981-03-27 |
Family
ID=14448781
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP10703279A Pending JPS5630677A (en) | 1979-08-22 | 1979-08-22 | Automatic luminance regulator |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS5630677A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5003300A (en) * | 1987-07-27 | 1991-03-26 | Reflection Technology, Inc. | Head mounted display for miniature video display system |
US5023905A (en) * | 1988-07-25 | 1991-06-11 | Reflection Technology, Inc. | Pocket data receiver with full page visual display |
US5048077A (en) * | 1988-07-25 | 1991-09-10 | Reflection Technology, Inc. | Telephone handset with full-page visual display |
-
1979
- 1979-08-22 JP JP10703279A patent/JPS5630677A/en active Pending
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5003300A (en) * | 1987-07-27 | 1991-03-26 | Reflection Technology, Inc. | Head mounted display for miniature video display system |
US5023905A (en) * | 1988-07-25 | 1991-06-11 | Reflection Technology, Inc. | Pocket data receiver with full page visual display |
US5048077A (en) * | 1988-07-25 | 1991-09-10 | Reflection Technology, Inc. | Telephone handset with full-page visual display |
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