Semiconductor Quadrichromatic Lamp for General Lighting

Abstract

A computer controlled 3000-lm quadrichromatic semiconductor lamp for general lighting with variable colour temperature and digital feedback is described. An optimal combination of colour rendering and luminous efficacy was found by selection of commercially available semiconductor emitters. LUXEONTM LXHL series emitters with the peak wavelengths of the spectral power distribution functions at 673 nm, 594 nm, 537 nm and 452 nm, respectively, were shown to provide appreciable values of the general colour rendering index (Ra>83) in the range of colour temperatures from 2856 K to 6504 K. The colour temperature and luminous flux of the lamp is controlled by computer by setting the durations of the light flux pulses for each group of primary emitters by a 10-bit digital circuit at a constant 300 Hz frequency of the pulses. The lamp contains a digital feedback circuit for the compensation of optical power variations of the primary-color LEDs with temperature and aging. Il. 6, bibl.6 (in Lithuanian; summaries in Lithuanian, English and Russian).