US3794424A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for determining the color or cut diamonds
Assignee: Individual
•
Filing: 1971-03-04
•
Granted: 1974-02-26
•
Expires: 1991-03-04
Abstract
Abstract The diamond is held by a well known holder below its holder or mounting edge leaving its upper portion with the planar surface and the facets fully exposed. A light ray of a predetermined wave length entering the diamond through the upper planar surface is totally reflected within the diamond in accordance with the geometric configuration of rays and emerging from the facets of the diamond. The amount of attenuation between the entering and the emerging light ray is measured photoelectrically, whereby attenuations of the entering light ray caused by surface reflections and by varying adjustments of the diamond are avoided.
Inventors
- 👤 M Eickhorst
- 👤 G Lenzen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:35
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/389; G01J; G01J3/00; G01J3/46; G01J3/50; G01J3/51; G01N21/00; G01N21/84; G01N21/87; G01J3/501
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
78 words
An apparatus for determining the color of cut diamonds of any cut pattern comprising in combination and in functional series arrangement means for generating selective light beams of at least two defined wave lengths, a light conductor for such rays, a holder for the cut diamond, an optical transmitter receiving the rays which are totally reflected within the diamond, a photoelectric receiver, and an electronic circuit fed by said receiver and including a register for the measured value.
Claim 2
Independent Claim
78 words
An apparatus for determining the color of cut diamonds of any cut pattern comprising in combination and in functional series arrangement means for generating selective light beams of at least two defined wave lengths, a light conductor for such rays, a holder for the cut diamond, an optical transmitter receiving the rays which are totally reflected within the diamond, a photoelectric receiver, and an electronic circuit fed by said receiver and including a register for the measured value.
Claim 3
Dependent Claim
65 words
An apparatus as claimed in claim 1, wherein the light conductor for the incident rays, the holder for the diamond, and the optical transmitter constitute a structural unit, wherein the emerging surface of the light conductor and the entrance surface of the transmitter are disposed in an optical planar common plane against which the upper planar surface of the diamond is biased in contacting engagement.
Claim 4
Dependent Claim
26 words
An apparatus according to claim 2, wherein the space formed between the surface of the holder and the optical planar plane is closed by a mirror.
Claim 5
Dependent Claim
20 words
A apparatus as claimed in claim 2, wherein the light conductor is at least partly disposed within the optical transmitter.
Claim 6
Dependent Claim
20 words
An apparatus as claimed in claim 2, wherein the light conductor and the optical transmitter consist of flexible fibrous optics.
Claim 7
Dependent Claim
21 words
An apparatus as claimed in claim 2, wherein the light conductor and the optical transmitter consist of encased light conducting rods.
Claim 8
Dependent Claim
21 words
An apparatus as claimed in claim 1, wherein the photoelectric receiver is a variably controllable element with respect to its sensitivity.
Claim 9
Dependent Claim
20 words
An apparatus in accordance with claim 6, wherein said light conductor is located within and surrounded by said optical transmitter.
Claim 10
Dependent Claim
21 words
An apparatus as claimed in claim 1, wherein the photoelectric receiver is a variably controllable element with respect to its amplification.
Claim 11
Dependent Claim
106 words
An apparatus as claimed in claim 1, wherein the electronic circuit comprises a demodulator controlled by said means for generating selective light beams of at least two defined wave lengths, said means being in the form of a rotatable filter wheel, said demodulator splitting the output signals of the photoelectric receiver, two channels receiving the split signals, adjustable resistance means in one of the two channels, and a regulator in the other of the two channels, a set-point adjustment, said regulator being connected to said set-point adjustment and back-coupled to said photo-electric receiver, whereby the two channels are coupled to the register for the measured values.
Claim 12
Independent Claim
83 words
A method for determining the color of cut diamonds of any cut pattern, especially the pattern of a brilliant cut, comprising the steps of projecting beams of at least two defined predetermined wave lengths of monochromatic light one after the other into the planar upper surface of the diamond being examined, and measuring photoelectrically the amount of attenuation of two reflected beamS emerging from the facets of the upper side of the diamond parallel to and in opposite direction to the projected beams.
Claim 13
Independent Claim
83 words
A method for determining the color of cut diamonds of any cut pattern, especially the pattern of a brilliant cut, comprising the steps of projecting beams of at least two defined predetermined wave lengths of monochromatic light one after the other into the planar upper surface of the diamond being examined, and measuring photoelectrically the amount of attenuation of two reflected beamS emerging from the facets of the upper side of the diamond parallel to and in opposite direction to the projected beams.
Claim 14
Dependent Claim
57 words
A method for determining the color of cut diamonds according to claim 11, wherein monochromatic light beams of more than two wave lengths are used for measuring, one wave length including the maximum absorption of the diamond at lambda 415,5 nm, while the other wave lengths are within the range of the visible spectrum above 500 nm.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-25 | 1977-08-27 | 1978-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-25 | 1981-08-27 | 1982-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-25 | 1985-08-27 | 1986-02-26 | $7700.00 | Window Closed / Lapsed |