A RELATIVE FLUX SENSOR AND A METHOD OF DETERMINING A RATIO BETWEEN MAXIMUM LIGHT INTENSITIES, A CONTROL DEVICE, A COLOR TUNABLE LAMP, A LUMINAIRE AND A COMPUTER PROGRAM PRODUCT

摘要

A relative flux sensor (122) and a method of characterizing characteristics of light emitters are provided. The relative flux sensor (122) comprises a color point sensor (108) and a sensor color (118). The color point sensor (108) measures a color point in a color space of light emitted by a light source (101) comprising a first light emitter (102) for emitting light of a first color and a second light emitter (114) for emitting light of a second color being different from the first color. The light source (101) is arranged for emitting light of a controllable color, being a mix of light of the first color and light of the second color. The sensor controller (118) is coupled to the color point sensor (108) for receiving a measuring signal and is arranged for i) providing a first signal to the light source (101), the first signal comprising a dimming factor D1 and a dimming factor D2, the dimming factor D1 and the dimming factor D2 indicating a fraction of a maximum flux of the first light emitter (102) and the second light emitter (114), respectively, and receiving the measuring signal representing a first color point when the light source (101) emits light according to the first signal, wherein at least one of the dimming factors D1 and D2 is different from 0, ii) providing a second signal to the light source (101), the second signal comprising a dimming factor D4 and a dimming factor D5, the dimming factor D4 and the dimming factor D indicating a fraction of the maximum flux of the first light emitter (102) and the second light emitter (114), respectively, and receiving the measuring signal representing a second color point when the light source (101) emits light according to the second signal, wherein both dimming factors D4 and D5 are different from 0, iii) calculating within a model of the color 20 space a ratio between a maximum flux of the first light emitter (102) and a maximum flux of the second light emitter (114) on the basis of the first color point, the second color point, the dimming factors D1, D2, D4 and D5.