← Back to Patent Explorer
US4636082A Expired / Lapsed US ⏱️ 0.0 years remaining

Fiber optic reflectance measurement apparatus

Assignee: GARDY DAVID J
•
Filing: 1983-07-01
•
Granted: 1987-01-13
•
Expires: 2003-07-01
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract To be certain of an even illumination of a field of measurement for measuring reflectance and to make it possible to have reflectance measuring heads of small size, the said field is illuminated with a number of discrete beams coming from transmitters, whose emission faces or areas are placed in a plane that is parallel to the plane of the said field. Preferably light guide cables are used for the transmitters and receivers.

Inventors

  • 👤 Jurgen Barry

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 10:09
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/47; G01N21/4738; G01N21/474

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 213 words
In an apparatus for measuring reflectance at a reflecting surface placed in a field of measurement, comprising a transmitted light guide cable made up of a number of light guide fibers for emission of a plurality of discrete beams along a transmitted light cone axis and a received light guide cable made up of a number of light guide fibers for receiving radiation reflected from said field of measurement along a received light cone axis, the light guide fibers of the transmitted and received light guide cables having transmitting and inlet faces respectively, the transmitted and received light cone axes passing through geometrical middle points of the respective transmitting and inlet faces, said transmitting faces of the transmitted light guide fibers and said inlet faces of the received light guide fibers being positioned in planes parallel to the plane of said field of measurement, the transmitted and received light cone axes meeting at a geometrical middle point of the surface to be measured, the transmitting face of the transmitted light guide cable and the inlet face of the received light guide cable having a form the same as the form of the surface to be measured, the transmitted and received light guide cables having aperture angles of less than 15° and 30+ respectively.
Claim 2
Dependent Claim 213 words
In an apparatus for measuring reflectance at a reflecting surface placed in a field of measurement, comprising a transmitted light guide cable made up of a number of light guide fibers for emission of a plurality of discrete beams along a transmitted light cone axis and a received light guide cable made up of a number of light guide fibers for receiving radiation reflected from said field of measurement along a received light cone axis, the light guide fibers of the transmitted and received light guide cables having transmitting and inlet faces respectively, the transmitted and received light cone axes passing through geometrical middle points of the respective transmitting and inlet faces, said transmitting faces of the transmitted light guide fibers and said inlet faces of the received light guide fibers being positioned in planes parallel to the plane of said field of measurement, the transmitted and received light cone axes meeting at a geometrical middle point of the surface to be measured, the transmitting face of the transmitted light guide cable and the inlet face of the received light guide cable having a form the same as the form of the surface to be measured, the transmitted and received light guide cables having aperture angles of less than 15° and 30+ respectively.
Claim 3
Dependent Claim 54 words
The apparatus as claimed in claim 1 wherein the said transmitted light guide cable is so placed that an axis thereof is at a selected angle to a line normal to said field of measurement, said transmitting faces of the said transmitted light guide fibers being ground and polished at this said selected angle.
Claim 4
Dependent Claim 68 words
The apparatus as claimed in claim 2 wherein said selected angle is equal to β that is given by the equation n.sub.i sin β=sin σ wherein σ is the angle between the axis of a light cone of a light guide fiber and the said line normal to the field of measurement and n i is the index of refraction of core material of said light guide fibers.
Claim 5
Independent Claim 38 words
The apparatus as claimed in claims 1 or 2 or 3 wherein the inlet faces of the received light guide fibers and a transmitting face of the transmitting light guide cable being in one and the same plane.
Claim 6
Dependent Claim 31 words
The apparatus as claimed in claim 1 further comprising a diaphragm for limiting the field of measurement to an area no greater than either the transmitting face or the inlet face.
Claim 7
Dependent Claim 29 words
The apparatus as claimed in claim 1 wherein said received light cone axis of the received light guide cable is a line normal to the surface to be measured.
Claim 8
Dependent Claim 32 words
The apparatus as claimed in claim 1 wherein an angle between an axis of the transmitted beam and a line normal to the field of measurement is in substance equal to 45°.
Claim 9
Dependent Claim 27 words
The apparatus as claimed in claim 5 further comprising a glass plate with said diaphragm thereon, said glass plate functioning as a support face for reflecting material.
Claim 10
Independent Claim 33 words
The apparatus as claimed in claims 1 or 5 wherein said transmitting face of the transmitted light cable is at least equal in size to the size of the surface to be measured.
Claim 11
Dependent Claim 32 words
The apparatus as claimed in claim 9 wherein said receiving face of the received light guide cable is at least equal in size to the size of the surface to be measured.
Claim 12
Dependent Claim 39 words
The apparatus as claimed in claim 1 wherein said transmitted light guide cable has its place taken by said received light guide cable and said received light guide cable has its place taken by said transmitted light guide cable.
Claim 13
Dependent Claim 196 words
In an apparatus for measuring reflectance at a reflecting surface placed in a field of measurement, comprising a transmitted light guide cable made up of a number of light guide fibers for emission of a plurality of discrete beams and a received light guide cable made up of a number of light guide fibers for receiving radiation reflected from said field of measurement, the light guide fibers of the transmitted and received light guide cables having transmitting and inlet faces respectively, said transmitting faces of the transmitted light guide fibers and said inlet faces of the received light guide fibers being positioned in planes parallel to the plane of said field of measurement so the transmitting face of the transmitted light guide cable and the receiving face of the received light guide cable have a form the same as the form of the surface to be measured, a glass plate acting as a support face for the reflecting surface, and a diaphragm, mounted to the glass plate, for limiting the field of measurement to a chosen size, the chosen size being equal to or smaller in area than either the transmitting face or the inlet face.
Claim 14
Dependent Claim 196 words
In an apparatus for measuring reflectance at a reflecting surface placed in a field of measurement, comprising a transmitted light guide cable made up of a number of light guide fibers for emission of a plurality of discrete beams and a received light guide cable made up of a number of light guide fibers for receiving radiation reflected from said field of measurement, the light guide fibers of the transmitted and received light guide cables having transmitting and inlet faces respectively, said transmitting faces of the transmitted light guide fibers and said inlet faces of the received light guide fibers being positioned in planes parallel to the plane of said field of measurement so the transmitting face of the transmitted light guide cable and the receiving face of the received light guide cable have a form the same as the form of the surface to be measured, a glass plate acting as a support face for the reflecting surface, and a diaphragm, mounted to the glass plate, for limiting the field of measurement to a chosen size, the chosen size being equal to or smaller in area than either the transmitting face or the inlet face.

References Cited (Backward Citations)

US3806256A Cited
US4033698A Cited
US4101222A Cited
US4464054A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-01-12 1990-07-14 1991-01-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-01-12 1994-07-14 1995-01-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-01-12 1998-07-14 1999-01-13 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag