| 摘要 |
PROBLEM TO BE SOLVED: To effectively control the heat generation at the distal end of an endoscope by efficiently diffusing the heat generated from a light emitting diode disposed for illuminating an observed object over the whole distal end. SOLUTION: Five LED parts L<SB>1</SB>-L<SB>5</SB>are disposed around an observation window 16a on the distal end face of the endoscope distal end 10A so that the quantity of light exceeding the maximum light quantity necessary for illuminating the observed object can be output on the whole. The LED parts are divided, for example, into a group A including three LED parts L<SB>1</SB>, L<SB>3</SB>and L<SB>5</SB>and a group B including two LED parts L<SB>2</SB>and L<SB>4</SB>. By controlling the lighting while switching the groups A and B, the temperature of the distal end 10A is controlled lower than a prescribed temperature, for example, 42°C. At the time, the LED parts belonging to the group A with larger influence of heat generation on an imaging module M can be lighted for a period shorter than the LED parts in the group B, and the LED parts L<SB>2</SB>and L<SB>4</SB>in the group B with a smaller number of LED parts can output a larger quantity of light than the LED parts L<SB>1</SB>, L<SB>3</SB>and L<SB>5</SB>in the group A. The quantities of output light may be uniform in the groups A and B. COPYRIGHT: (C)2008,JPO&INPIT
|
