Thermal radiation sensor

US5010315A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Horst Fedter · Bühlertal, DE
• Werner Grunwald · Gerlingen, DE
• Peter Nolting · Bühl, DE
• Claudio De La Prieta · Stuttgart, DE
• Kurt Schmid · Ditzingen, DE

Key dates

• Filing date: Aug 18, 1989
• Grant date: Apr 23, 1991
• Expiry date: Aug 18, 2009

Classification

• Technology area (CPC G): Physics
• CPC primary: G01J5/20
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A thermal radiation sensor is suggested which comprises two receiver surfaces exposed to the radiation, one receiver surface (1) having a high absorption capacity with respect to the thermal radiation, the other (2) having a low absorption capacity, the two receiver surfaces (1) and (2) consist of a NTC resistance material and are combined in a bridge circuit together with two temperature-independent cermet resistors (3) and (4). In order to prevent a dependency of the measurements of such a sensor on the ambient temperature, the NTC resistors (1) and (2) comprise underlying heating layers (6) and (7) which keep the two NTC resistors at a constant temperature. Insulating layers (8) and (9) are provided between the NTC resistors (1) and (2) and the heating layers (6) and (7). The heating layers (6) and (7) consist of a cermet thick film with platinum or of a platinum thick film and have the shape of a meander. The insulating layers (8) and ( 9) preferably consist of a crystallizing glass.