公开(公告)号：US3923401A

公开(公告)日：1975-12-02

申请号：US43469874

申请日：1974-01-18

Applicant: SOPELEM

Inventor： LLOP HELENIO ,  LEFORT PIERRE

IPC: G01N21/43 ,  G01N21/46

CPC classification number: G01N21/43

Abstract: Apparatus yeilding an electrical signal representative of the position of a boundary line between adjacent light and dark zones, with respect to a reference position, comprises two photoelectric cells having a separation in the direction in which the boundary moves. Means are provided whereby the output P1 of that one of the photocells which is last reached by the boundary during its movement is multiplied by a constant k, yielding a signal K.P1 which, together with the signal P2 from the other photocell, is applied to a difference amplifier providing an output signal which passes through zero when K.P1 P2. This signal may be applied to one input of a second difference amplifier, receiving also an output of a third differential amplifier providing a negative signal whenever P2 is less than a predetermined value. The final output signal may be applied to control traversal of the assembly including the two photocells, so as to obtain a measure of the boundary displacement.

Abstract translation: 相对于参考位置，代表相邻光和暗区域之间的边界线的位置的电信号的装置包括在边界移动的方向上具有间隔的两个光电单元。 提供了这样的装置，其中在其移动期间由边界最后到达的光电单元的一个的输出P1乘以常数k，产生信号K.P1，其与来自另一个光电池的信号P2一起被应用 提供一个差分放大器，当K.P1 = P2时提供通过零的输出信号。 该信号可以被施加到第二差分放大器的一个输入端，每当P2小于预定值时也接收提供负信号的第三差分放大器的输出。 可以应用最终输出信号来控制包括两个光电管的组件的遍历，以便获得边界位移的量度。