US 7,071,472 B2 · Irradiation control device

Abstract

In an irradiation control device which extends a longevity of an LED, a feedback control is performed to an irradiating portion by an output signal of a photo device provided in relation to the irradiating portion, thereby making brightness fixed. Alternatively, by performing image processing to an image taken by a camera, brightness on a screen is calculated, so that a feedback control is performed to the irradiating portion to make the brightness fixed. Alternatively, based on a recognition rate upon character recognition within the image taken by the camera, a feedback control is performed to the irradiating portion to make the brightness fixed.

Claims12

Dependent claims

An irradiation control device comprising:

an irradiating portion having an LED;
a photo device receiving an output light of the LED;
a light quantity measuring portion measuring a light quantity of the LED from an output signal of the photo device;
and
a controller controlling the irradiating portion based on the measured light quantity, keeping the light quantity of the LED at a predetermined minimum fixed level required for recognizing a subject irradiated by the irradiating portion.

2 more elements

Dependencies are inferred from the claim text.

Irradiation control device

Life of this patent

Irradiation control device

Life of this patent

Abstract

Claims12