| 摘要 |
PURPOSE:To minimize the influence of the heat of a light source to a photoreceptor element, by bending the luminous flux for detection of an optical pickup for at least two times by means of reflecting members and separating farther the photoreceptor element from the light source. CONSTITUTION:A luminous flux for detection coming out from a condenser lens 7 is bent by a reflecting member 12 at a right angle after it is once bent at a right angle so that it can become parallel with a luminous flux for irradiation by another reflecting member 11, and made incident to a photoreceptor element 9. If it is arranged that the luminous flux for the reflecting member 12 can intersect the luminous flux for irradiation, the entire body of this pickup can be miniaturized extremely. The installing location of a track detecting photoreceptor element 8 is not limited to the location between the condenser lens 7 and reflecting member 11 only as shown in the figure, but the element 8 cen be set between the reflecting members 11 and 12 or between the reflecting member 12 and focal point detecting photoreceptor element 9 also. |
