Patent · US Expired

Device for detecting a transmissivity of a substance

US4898462A · kind A · utility

9Cited by
8References
13Claims
0Family size

Assignees

Inventors

Key dates

Filing dateFeb 25, 1988
Grant dateFeb 6, 1990
Priority date
Expiry dateFeb 25, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N2201/1212
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A device for detecting a transmissivity of a substance utilizing a transmitted light value, which comprises a light emitting element and a photo detecting element. The light emitting element and the photo detecting element are spaced from each other at a predetermined distance so that a transmitted light value of a substance passing through the space is detected as an amount of light transmitted therethrough. The photo detecting element further comprises a photo oscillator circuit including the photo detecting element as one component thereof and outputs a signal having characteristics selected from a cycle and a frequency corresponding to the transmitted light value, and when the condition of a substance exceeds a predetermined reference level, such information is displayed at a display unit. Further, the device carries out a detecting and discriminating operation when a temperature of a substance is at a level lower than a maximum temperature at which each component of the detecting circuit will not work effectively. The device is also provided with a detecting unit in which the light emitting element and the photo detecting element are kept firmly in contact with each other, wit…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.