Optical vacuum pressure gauge

Details Optical vacuum pressure gauge Optical vacuum pressure gauge

1997-11-12

1999-06-01

Oen, William

Measuring and testing

Fluid pressure gauge

Photoelectric

25023119, G01L 900, G01J 156, G01J 546

Patent

active

059089881

ABSTRACT:
An incident ray is emitted into a vacuum probe manufactured by a transparent material inside a cavity and is totally reflected according to the invention. Based on Fresnel's equation, when an angle of incidence is fixed, the phase difference between a s-polarized light and p-polarized light is a function of two refractive indexes on the both sides of an interface. Therefore, when the refractive index of gas inside the cavity varies with pressure therein, the phase difference between the s-polarized light and p-polarized light can be measured by a total-internal-reflection heterodyne interfermetry. Next, the refractive index of the vacuum cavity can be estimated based on the variation of the phase difference. Then, the pressure inside the cavity is obtained from the measured refractive index of the vacuum cavity cooperating a known pressure contrast list, so that vacuum degree inside the cavity is known.

REFERENCES:
patent: 4342907 (1982-08-01), Macedo et al.
patent: 4443700 (1984-04-01), Macedo et al.
patent: 4729240 (1988-03-01), Sugihara
patent: 4752141 (1988-06-01), Sun et al.
M. Bom et al., "Principles of Optics," 6.sup.th Ed., Pergamon Press, Oxford, U.K., pp. 48-50 (1980). (No month).
A. Wang et al., "Split-spectrum intensity-based optical fiber sensors for measurement of microdisplacement, strain, and pressure," Applied Optics, 35(15):2595-2601 (May 20, 1996).

Affiliated with

Also associated with

Rating

Optical vacuum pressure gauge does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Optical vacuum pressure gauge, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical vacuum pressure gauge will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-956139