IMPROVEMENTS IN AND RELATING TO DISPLAYS AND LIGHT SOURCES FOR DISPLAYS

摘要

A light source for a colour display apparatus (1) for displaying light at optical wavelengths corresponding a plurality of different colours sequentially, comprising a plurality of light-emitting diodes (3, 4, 5) each respectively operable to emit light to display a respective one of the plurality of different colours, a power source (26) connected to the plurality of LEDs for supplying power thereto a plurality of capacitor units (7, 8, 9) connected to the power source to be provided thereby with charge for generating a respective one of a plurality of different respective forward bias voltages for application to the LEDs to operate the LED. A control unit (10) is operable to selectively connect a capacitor unit to an LED for applying a desired one of the different said forward bias voltages thereto according to the colour of light which the LED is operable to display.

主权项

1. A light source for a colour display apparatus for displaying light at optical wavelengths corresponding a plurality of different colours sequentially, the light source comprising:
a plurality of light-emitting diodes (LED) each respectively operable to emit light to display a respective one of said plurality of different colours; a power input part for connecting the plurality of LEDs to a power supply for supplying power thereto, the power input part including a plurality of current sensing units, each current sensing unit being selectable in respect of one of the plurality of LEDs to apply a corresponding limit to the level of current that may be supplied thereto by the power supply; a plurality of capacitor units connected to the power input part to be provided with charge from a said power supply for generating a respective one of a plurality of different respective forward bias voltages for application to said LEDs to operate the LEDs; and a control unit operable to connect selectively a said capacitor unit to a said LED for applying a desired one of said different said forward bias voltages thereto according to the colour of light which the LED is operable to display and to select a corresponding one of said plurality of current sensing units for the LED.