Title:
STROBOSCOPIC DEVICE
Document Type and Number:
Japanese Patent JP3392903
Kind Code:
B2
Abstract:
PURPOSE: To improve the characteristic of light distribution and to increase a guide number defined by the light quantity of a central part by constituting a reflecting surface to be a shape that the virtual image of a light source is formed on the back surface thereof.
CONSTITUTION: Luminous flux reflected on the second reflecting surface 12a positioned on an upper side out of the luminous flux emitted from the light emitting center 11a of a light emitting tube 11 proceeds in a direction (p). Besides, the luminous flux reflected on the second reflecting surface 12a positioned on a lower side out of the luminous flux emitted from the center of the tube 11 proceeds in a direction (q). Therefore, points (a) and (b) being at a position optically conjugated with the center of the tube 11 as for the reflecting surface 12a are equivalent to the case that there is the virtual image of the light emitting center of the tube 11. Then, the luminous flux is emitted just as if it is emitted from the light emitting tubes 11' and 11" that the points (a) and (b) are taken as the light emitting center. Besides, since the images of the luminous flux (p) and (q) are not formed after they are passed through a Fresnel lens and the luminous flux (p) and (q) can be directly emitted in an identical direction, the uniform light distrubution without causing unevenness near the center is obtained.
Inventors:
Go Ishikawa
Application Number:
JP7796693A
Publication Date:
March 31, 2003
Filing Date:
April 05, 1993
Export Citation:
Assignee:
Pentax Corporation
International Classes:
G02B5/08; G03B15/02; G03B15/05; (IPC1-7): G03B15/05; G02B5/08
Domestic Patent References:
| JP5142629A | ||||
| JP4138438A | ||||
| JP349536U |
Attorney, Agent or Firm:
Kunio Miura
Previous Patent: INJECTION MOLDED PIECE HAVING HOLLOW RIB STRUCTURE
Next Patent: METHOD AND DEVICE FOR LENS TILT ADJUSTMENT
Next Patent: METHOD AND DEVICE FOR LENS TILT ADJUSTMENT