Optical measurement probe, and optical measurement device provided with the same

Patent metadata

Field	Value
Publication number	US-9239298-B2
Application number	US-201414481230-A
Country	US
Kind code	B2
Filing date	Sep 9, 2014
Priority date	Sep 20, 2013
Publication date	Jan 19, 2016
Grant date	Jan 19, 2016

Abstract

There are provided an optical measurement probe capable of obtaining a more stable measurement result, and an optical measurement device provided with the same. An incidence surface of an optical window to be used in a high temperature environment is covered by a deposited film. The optical window is formed of sapphire, and the deposited film is formed from SiO 2 . Adhesion of dirt to the incidence surface, and an influence, on a measurement result, of the adhesion of dirt on the incidence surface can thereby be prevented, and a more stable measurement result can be obtained.

First claim

What is claimed is:

1. An optical measurement probe structured to guide light generated in a high temperature environment to an appliance, comprising:
an optical window for transmitting light incident on an incidence surface; and
a light guide for guiding light which has passed through the optical window to the appliance,
wherein the incident surface of the optical window is covered by a deposited protective film which is formed from a lipophobic material and which protects the window from greasy dirt.

2. The optical measurement probe according to claim 1 , wherein the optical window is formed of sapphire.

3. The optical measurement probe according to claim 1 , wherein the deposited film is formed from SiO 2 .

4. The optical measurement probe according to claim 1 , wherein the deposited film is formed directly on the incidence surface.

5. The optical measurement probe according to claim 1 , wherein at least one layer of another film is interposed between the deposited film and the incidence surface.

6. The optical measurement probe according to claim 5 ,
wherein the at least one layer of another film is formed to cover an entire surface of the incidence surface of the optical window, and
wherein a multilayer film of the at least one layer of another film and the deposited film is formed on the entire surface of the incidence surface of the optical window.

7. An optical measurement device comprising:
the optical measurement probe according to claim 1 ; and
a detector for detecting light guided by the optical measurement probe.

8. An optical measurement device, wherein the optical measurement probe according to claim 1 is attached to a cylinder head of an internal combustion engine in such a way as to look into a combustion chamber that is a measurement target.

9. The optical measurement probe of claim 1 , wherein the probe is heat-resistant in an environment of 300° C. or higher.

10. The optical measurement probe of claim 1 , wherein the probe is heat-resistant in an environment of 800° C. or higher.

11. The optical measurement probe of claim 1 , wherein the deposited film is formed from TiO 2 .

12. The optical measurement probe of claim 1 , wherein the light guide is an optical fiber.

13. The optical measurement probe of claim 1 , further comprising a holder for accommodating the optical window at an end portion,
wherein the incident surface of the optical window is directed outward of the holder.

Assignees

• Shimadzu Corp
• Honda Motor Co Ltd

Inventors

• Nagai Tetsuya
• Iwai Nobuyuki
• Furukawa Yasuyuki
• Hiraoka Ryoji
• Azumagakito Isao
• Okada Satoru

Classifications

• G02B1/14

  Protective coatings, e.g. hard coatings · CPC title

• G01N2201/08

  Optical fibres; light guides · CPC title

• G01N21/15

  Preventing contamination of the components of the optical system or obstruction of the light path · CPC title

• G01D5/353

  influencing the transmission properties of an optical fibre · CPC title

• H01T13/40

  structurally combined with other devices (combined or associated with fuel injectors F02M57/06; structurally combined with other parts of internal-combustion engines F02P13/00) · CPC title