Patent ID: 6870147

Claim:
A light stability testing device comprising: a light source; an optical system for regulating light rays emitted from this light source; a sample stage for placement of a sample onto which light rays passed through this optical system are to be irradiated; a light measuring sensor for measuring the dose of light rays, attached to this sample stage; and a control unit to which a signal from this light sensor is transmitted and which controls said optical system, wherein said light sensor comprises a visible light measuring sensor for measuring the dose of visible light and an ultraviolet measuring sensor for measuring the dose of ultraviolet rays, said optical system comprises a total light regulating means for regulating the absolute quantity of light rays emitted from said light source and an ultraviolet regulating means for regulating the dose of ultraviolet rays of light rays, and said control unit comprises a total light control portion for controlling said total light regulating means by a signal from said visible light measuring sensor and an ultraviolet control portion for controlling said ultraviolet regulating means by a signal from said ultraviolet measuring sensor.