FLUORESCENT LIGHT TEMPERATURE SENSOR

• US 20090261751A1
• Filed: 04/16/2009
• Published: 10/22/2009
• Est. Priority Date: 04/21/2008
• Status: Active Grant

• Current Assignee: Azbil Corporation (Azbil BioVigilant Incorporated)
• Original Assignee: Yamatake Corporation
• Inventors: Kato, Atsushi, Kinugasa, Seiichiro, Ichida, Shunji
• Granted Patent: US 8,193,726 B2
• Time in Patent Office: Days
• US Class Current: 315/293
• CPC Class Codes: G01K 11/3213 using changes in luminescence, e.g. at the distal end of the fibres

Abstract

A fluorescent light temperature sensor for producing a temperature signal from a fluorescent light of an optically stimulated fluorescent material is provided with: an LED for projecting light onto the fluorescent material; a driving circuit for driving the light projecting element; a photo diode for receiving the fluorescent light that is emitted from the fluorescent material; a signal processing circuit for producing the temperature signal from the output signal from the photo diode; and an APC circuit for controlling the driving of the driving circuit so as to maintain a uniform light projecting intensity from the LED based on the output signal of the photo diode.

Claims

1. A fluorescent light temperature sensor for generating a temperature signal from a fluorescent light from an optically stimulated fluorescent material, comprising:

a light projecting element projecting light onto the fluorescent material;

a driving circuit driving the light projecting element;

a light receiving element receiving fluorescent light emitted from the fluorescent material;

a signal processing circuit generating a temperature signal from the output signal of the light receiving element; and

a controlling circuit controlling the driving of the driving circuit through sending a control signal to the driving circuit so as to maintain a uniform intensity for the fluorescent light of the fluorescent material based on the output signal from the light receiving element.

2. The fluorescent light temperature sensor as set forth in claim 1, wherein:

the driving circuit drives the light projecting element so as to project light at uniform intervals; and

the controlling circuit controls the intensity of the projected light in one cycle based on the intensity of the fluorescent light of the fluorescent materials due to the projected light in the previous cycle.

3. A fluorescent light temperature sensor as set forth in claim 1, comprising:

evaluating device for evaluating the service life of the light projecting element in advance based on a control signal from the controlling circuit.

4. A fluorescent light temperature sensor as set forth in claim 3, wherein:

the evaluating device evaluates the service life of the light projecting element in advance based on the frequency of outputting of the control signal per unit time.

5. A fluorescent light temperature sensor as set forth in claim 3, wherein:

the evaluating device evaluates the service life of the light projecting element in advance based on a controlled variable expressed by the control signal.

6. A fluorescent light temperature sensor as set forth in claim 3, comprising:

evaluating means device for evaluating the service life of the light projecting element in advance based on a control signal from the controlling circuit.