公开(公告)号：US3771877A

公开(公告)日：1973-11-13

申请号：US3771877D

申请日：1972-02-14

Applicant: SARGENT WELCH SCIENTIFIC CO

Inventor： ROSENCRANZ R

IPC: G01J1/24 ,  G01N21/47 ,  G01J3/48 ,  G01J1/42 ,  G01N21/48

CPC classification number: G01N21/474 ,  G01J1/24

Abstract: An instrument for determining optical density by measurement of diffuse reflected light. The instrument includes a light source, means for forming a beam of diffuse reflected light, an electrical balancing circuit, and an optical attenuator for controlling the intensity of light incident on a photoresponsive element forming a part of the balancing circuit. In the use of the instrument, the units of optical density are read directly from the optical attenuator, and mechanical movement thereof serves to provide an aperture of increased or decreased size, admitting more or less light, until electrical balance is achieved in the circuit. A balanced circuit condition is indicated by extinguishment of a single bulb, and the reading is taken only when the balanced condition occurs. In the preferred form of construction, the optical attenuator is in the form of a disc or wheel having a gradually increasing opening therein, and adapted for direct manipulation by the operator. Calibration of the instrument is achieved by illuminating a standard or known control specimen, and adjusting a nulling potentiometer in a balancing bridge to produce a balanced condition in the circuit. By using a mechanical attenuator instead of an electrical signal strength control, the unit is simplified in construction and is more accurate and reliable in use.

Abstract translation: 用于通过测量漫反射光来确定光密度的仪器。 仪器包括光源，用于形成漫反射光束的装置，电平衡电路和用于控制入射到形成平衡电路的一部分的光响应元件上的光的强度的光衰减器。 在使用仪器时，光密度的单位直接从光衰减器读取，其机械运动用于提供增加或减小尺寸的孔，允许或多或少的光，直到在电路中实现电平衡。 通过熄灭单个灯泡表示平衡电路状况，只有当平衡状况发生时才进行读数。 在优选的结构形式中，光衰减器是其中具有逐渐增加的开口的盘或轮的形式，并且适于由操作者直接操纵。 仪器的校准是通过照亮标准或已知的对照样品，并调整平衡桥中的归零电位器来产生电路中的平衡状态来实现的。 通过使用机械衰减器代替电信号强度控制，该装置结构简化，使用更准确可靠。