公开(公告)号：US3653772A

公开(公告)日：1972-04-04

申请号：US3653772D

申请日：1969-08-19

Applicant: GAF CORP

Inventor： BERGE RALPH L

IPC: G01J1/30 ,  G01N21/25 ,  G01N21/22 ,  G01N21/48

CPC classification number: G01N21/256 ,  G01J1/30

Abstract: Two lamps are lighted alternately at controlled intensities, both lamps illuminate a common sensor and the light path from one lamp includes the density to be measured. When a minimum differential is detected, the ratio of the currents in the lamps is a function of the density being measured and current in either one or both lamp is servo-controlled to minimize the differential. The current or voltage ratios are converted and read out as density values.

Abstract translation: 两个灯以受控的强度交替点亮，两个灯照亮一个共同的传感器，并且来自一个灯的光路包括待测量的密度。 当检测到最小差分时，灯中的电流比是测量的密度的函数，并且在一个或两个灯中的电流被伺服控制以最小化差分。 电流或电压比被转换并读出作为密度值。