Sensing system

申请公布号：

DE3440157(A1)

申请号：

DE19843440157

申请日期：

1984.11.02

申请公布日期：

1986.05.07

申请人：

OPTISCHE WERKE G. RODENSTOCK

发明人：

ROTHE,ERNST

分类号：

G02B13/00;G02B26/10;G02B27/00;(IPC1-7):G02B26/10;G02B13/24;G02B27/30;G11B7/08

主分类号：

G02B13/00

摘要：

A sensing system is described, with a light source (1), with a collimator objective (2) which collects the light of the light source, with a sensing objective (3) which images the light collected from the collimator objective (2) on a surface (4) to be sensed, and with a mirror (5) which is arranged between collimator objective and sensing objective, which mirror, in order to obtain smaller sensing movements on the surface (4) to be sensed, can be swivelled about the position in which it deflects the beam path of the sensing system by 90 DEG . Sensing systems of this kind are used for example in video disk players. According to the invention, the collimator objective has a maximum of only two lenses with a positive refractive power, the shutter 6 of the sensing system being arranged in the sensing objective 3. The sensing objective according to the invention has a consciously introduced spherical aberration and coma which compensate the spherical residual aberration of the collimator objective, which is non-correctable due to the selected structure, for all the positions of the mirror. The spherical aberration of the collimator objective actually acts in specific positions of the mirror like an additional asymmetry error. The sensing system according to the invention can be used in a virtually diffraction-limited fashion for all positions of the mirror 5 occurring during operation. <IMAGE>