Circuit comprising a combined signal and environmental light sensor
View Patent ↗In indication and image reproduction apparatus, the ambient brightness must be taken into account for an optimum reproduction quality. This requires an optical sensor, which is associated with additional technical outlay. The invention relates to a circuit which allows the ambient brightness to be determined by means of a sensor that is already present in the device, for the reception of data or control signals. In particular for apparatus appertaining to consumer electronics.
1. An apparatus, comprising:
an optical sensor for receiving optical signals and converting said optical signals into electrical signals;
a regulating arrangement for counteracting a saturation of said optical sensor;
a drive circuit operatively coupled to said optical sensor, said drive circuit including a first output line for providing a first electrical signal representing said optical signals received by said optical sensor at a first rate of change, and a second output line for providing a second electrical signal representing said optical signals received by said optical sensor at a second rate of change; and
wherein said second electrical signal controls at least one operating parameter of an indication device.
2. The apparatus of claim 1 , wherein:
said drive circuit further includes filtering means for separating said electrical signals provided from said optical sensor into said first and second electrical signals; and
said first rate of change is greater than said second rate of change.
3. The apparatus of claim 1 , wherein said regulating arrangement adjusts current consumption of said optical sensor so that said first electrical signal is substantially independent of said second electrical signal.
4. The apparatus of claim 1 , wherein said at least one operating parameter includes brightness.
5. The apparatus of claim 1 , wherein said optical signals having said first rate of change correspond to command signals and said optical signals having said second rate of change represent ambient brightness.
6. An apparatus, comprising:
an infrared reception module for receiving optical signals and converting said optical signals into electrical signals, said infrared reception module including a first output for providing a first electrical signal representing said optical signals received by said infrared reception module at a first rate of change;
a control circuit for controlling current consumption of said infrared reception module, said control circuit including a second output for providing a second electrical signal responsive to said current consumption of said infrared reception module, said second electrical signal representing said optical signals received by said infrared reception module at a second rate of change; and
wherein said second electrical signal controls at least one operating parameter of an indication device.
7. The apparatus of claim 6 , wherein said control circuit includes a current mirror circuit for controlling said current consumption of said infrared reception module.
8. The apparatus of claim 7 , wherein:
said control circuit further includes filtering means operatively coupled to said current mirror circuit for providing at said second output only said second electrical signal; and
said first rate of change is greater than said second rate of change.
9. The apparatus of claim 6 , wherein said optical signals having said first rate of change correspond to command signals and said optical signals having said second rate of change represent ambient brightness.
10. The apparatus of claim 6 , wherein said at least one operating parameter includes brightness.
11. A method for controlling a display device, comprising steps of:
using an optical sensor to receive optical signals and convert said optical signals into electrical signals;
controlling current consumption of said optical sensor;
providing a first electrical signal representing said optical signals received by said optical sensor at a first rate of change;
providing a second electrical signal representing said optical signals received by said optical sensor at a second rate of change; and
using said second electrical signal to control at least one operating parameter of said display device.
12. The method of claim 11 , further comprised of separating said electrical signals provided from said optical sensor into said first and second electrical signals, and wherein said first rate of change is greater than said second rate of change.
13. The method of claim 11 , wherein said at least one operating parameter includes brightness.
14. The method of claim 11 , wherein said optical signals having said first rate of change correspond to command signals and said optical signals having said second rate of change represent ambient brightness.