Method and apparatus for illuminating an object with white light
AssigneeNokia Corporation
InventorMika Antila
Life of this patent
Estimating the term…
Abstract
A method and apparatus for illuminating an object with white light, in which method the object is illuminated using lights of at least two different colors. The intensities of the lights are measured and then the intensity of illumination provided by means of a light of a single color is adjusted on the basis of the measured intensities of illumination provided by means of at least two different colors to improve the white balance of the object's illumination.
Claims20
A method for producing white light for illuminating an object, in which method light of a first colour having a first luminous power and light of a second colour having a second luminous power are produced to illuminate the object, wherein the method comprises the steps of:
- measuring the first luminous power;
- measuring the second luminous power;
- and
- adjusting the white balance of the object's illumination by adjusting the first or the second luminous power on the basis of the measured luminous powers of the lights of the first and second colours, wherein the adjustment of the first luminous power comprises the sub-steps of:
- intermitting the producing of the light of the first colour so that it is on for only a proportion of the time the object is being illuminated;
- and
- adjusting said proportion to adjust the first luminous power.
An apparatus for illuminating an object with white light, the apparatus comprising:
- first illuminating means for producing light of a first colour having a first luminous power;
- second illuminating means for producing a light of a second colour having a second luminous power;
- means for measuring the first luminous power;
- means for measuring the second luminous power;
- and
- means for adjusting the white balance of the object's illumination by adjusting the first or second luminous power on the basis of the measured first and second luminous powers, wherein the adjusting the first luminous power comprises intermitting the producing of the light of the first colour so that it is on for only a proportion of the time the object is being illuminated and adjusting the proportion to adjust the first luminous power.
Dependencies are inferred from the claim text.