Patent US5051872A successfully refreshed from Google Patents.
US5051872A
Expired / Lapsed
US
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Hemispherical non-glare illuminator
Assignee: Texas Instruments Inc
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Filing: 1990-05-15
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Granted: 1991-09-24
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Expires: 2010-05-15
Abstract
Abstract A translucent hemispherical diffuser provides shadowless, uniform illumination of an object to be inspected or otherwise viewed. The optical medium of the translucent diffuser has a milk glass optical consistency, and/or one or more surfaces of the diffuser may be textured to diffuse light entering or leaving the optical medium of the diffuser. The hemispherical diffuser is placed between a light source and the object to be viewed. Light from the light source entering the optical medium of the diffuser is re-radiated uniformly from the concave surface of the diffuser. The object to be viewed is located approximately at the center of curvature of the hemispherical diffuser. Thus, the radiating concave surface of the diffuser subtends a solid angle of approximately two -pi steradians. Light may be scattered and diffused by various reflecting surfaces external to the diffuser, prior to entering the optical medium of the diffuser. One embodiment of the diffuser includes reflecting surfaces as an integral part of the diffuser. Light sources may be remote lamp and fiber optical systems, or local, spirally wound neon tubes covering the diffuser. Each diffuser includes a viewing port for observing the illuminated object. The viewing port may have associated with it a beam splitter or half silvered mirror assembly to direct light toward the object to prevent an image of the port from being reflected by the object, and to pass light reflected by the object to a video camera or other viewing device.
Inventors
- 👤 Charles H. Anderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:43
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/8806; F; F21; F21S; F21S8/00; G01N2021/8812
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
74 words
A diffuser assembly for shadowless illumination of an object comprising: a translucent diffuser having a substantially hemispherical, concave surface; a diverging lens spaced from, shaping and directing light onto said diffuser a light source positioned to direct light rays through said diverging lens and into the optical medium of said diffuser; wherein substantially all of the light rays incident at the center of the curvature of the concave surface pass through the translucent diffuser.
Claim 2
Dependent Claim
74 words
A diffuser assembly for shadowless illumination of an object comprising: a translucent diffuser having a substantially hemispherical, concave surface; a diverging lens spaced from, shaping and directing light onto said diffuser a light source positioned to direct light rays through said diverging lens and into the optical medium of said diffuser; wherein substantially all of the light rays incident at the center of the curvature of the concave surface pass through the translucent diffuser.
Claim 3
Dependent Claim
41 words
The diffuser assembly of claim 1, wherein said light source comprises: a lamp remote from said diffuser; and a fiber optical cable for conducting light from said lamp to said position to direct light into the optical medium of said diffuser.
Claim 4
Dependent Claim
22 words
The diffuser assembly of claim 1, further comprising: at least one reflector for reflecting light into the optical medium of said diffuser.
Claim 5
Dependent Claim
22 words
The diffuser assembly of claim 1, wherein: the optical medium of said diffuser has a milk glass optical consistency to diffuse light.
Claim 6
Dependent Claim
15 words
The diffuser assembly of claim 1, wherein: said concave surface is textured to scatter light.
Claim 7
Dependent Claim
14 words
The diffuser assembly of claim 5, wherein: said concave surface is a sandblasted surface.
Claim 8
Dependent Claim
14 words
The diffuser assembly of claim 5, wherein: said concave surface is an etched surface.
Claim 9
Dependent Claim
11 words
The diffuser assembly of claim 1, wherein: said diffuser is plastic.
Claim 10
Dependent Claim
11 words
The diffuser assembly of claim 1, wherein: said diffuser is glass.
Claim 11
Dependent Claim
24 words
The diffuser assembly of claim 1, wherein said diffuser further comprises: a convex surface positioned to receive said directed light from said light source.
Claim 12
Dependent Claim
26 words
The diffuser assembly of claim 10, wherein: said convex surface is textured to scatter said directed light as it enters the optical medium of said diffuser.
Claim 13
Dependent Claim
15 words
The diffuser assembly of claim 1, further comprising: a viewing port located in said diffuser.
Claim 14
Dependent Claim
25 words
The diffuser assembly of claim 1, wherein the diffuser assembly is symmetrical about an axis, further comprising: a viewing port off-axially located in said diffuser.
Claim 15
Independent Claim
86 words
A method of shadowless illumination of an object, comprising the steps: (a) providing a translucent diffuser having a substantially hemispherical, concave surface; (b) positioning an object to be illuminated near the center of curvature of said concave surface; and (c) directing substantially all light rays through a lens spaced from said diffuser to uniformly distribute the light rays into the optical medium of said diffuser, in a direction to cause light to be radiated uniformly from said concave surface toward said object, to illuminate said object.
Claim 16
Independent Claim
86 words
A method of shadowless illumination of an object, comprising the steps: (a) providing a translucent diffuser having a substantially hemispherical, concave surface; (b) positioning an object to be illuminated near the center of curvature of said concave surface; and (c) directing substantially all light rays through a lens spaced from said diffuser to uniformly distribute the light rays into the optical medium of said diffuser, in a direction to cause light to be radiated uniformly from said concave surface toward said object, to illuminate said object.
Claim 17
Dependent Claim
25 words
The method of claim 14, wherein step (b) includes the step: positioning said object to be illuminated, below the bottom edge of said concave surface.
Claim 18
Dependent Claim
24 words
The method of claim 14, wherein step (c) includes the step: providing reflectors positioned to reflect light into the optical medium of said diffuser.
Claim 19
Dependent Claim
19 words
The method of claim 14, wherein step (a) includes the step: providing a viewing port in said translucent diffuser.
Claim 20
Dependent Claim
18 words
The method of claim 17, further comprising the step: (d) viewing the illuminated object through said viewing port.
Claim 21
Dependent Claim
22 words
The method of claim 18, wherein step (d) includes the step: viewing said object through said viewing port with a video camera.
Claim 22
Dependent Claim
21 words
The method of claim 18, wherein step (d) includes the step: viewing said object through said viewing port with a microscope.
Claim 23
Dependent Claim
37 words
The method of claim 17, further comprising the step: (d) providing a means for directing light through said viewing port toward said object to prevent an image of said viewing port from being reflected from said object.
Claim 24
Dependent Claim
18 words
The method of claim 21, wherein: said directing means include means for passing light reflected from said object.
Claim 25
Dependent Claim
120 words
A diffuser assembly for shadowless illumination of an object, comprising: a translucent diffuser having a substantially hemispherical, concave surface; a light source for directing light rays into the optical medium of said diffuser; a lens positioned between and spaced from the light source and the diffuser for uniformly distributing the light rays on to the diffuser; a viewing port in said diffuser for viewing an object positioned near the center of curvature of said concave surface; and a means for directing light through said viewing port toward said object, and for passing light reflected from said object; wherein substantially all of the light rays incident at the center of the curvature of the concave surface pass through the translucent diffuser.
Claim 26
Dependent Claim
120 words
A diffuser assembly for shadowless illumination of an object, comprising: a translucent diffuser having a substantially hemispherical, concave surface; a light source for directing light rays into the optical medium of said diffuser; a lens positioned between and spaced from the light source and the diffuser for uniformly distributing the light rays on to the diffuser; a viewing port in said diffuser for viewing an object positioned near the center of curvature of said concave surface; and a means for directing light through said viewing port toward said object, and for passing light reflected from said object; wherein substantially all of the light rays incident at the center of the curvature of the concave surface pass through the translucent diffuser.
Claim 27
Dependent Claim
13 words
The diffuser assembly of claim 23, wherein: said means is a beam splitter.
Claim 28
Dependent Claim
13 words
The diffuser assembly of claim 23, wherein: said means is a half-silvered mirror.
Claim 29
Dependent Claim
24 words
The diffuser assembly of claim 23, wherein: said means includes a reflecting surface positioned to reflect light through said viewing port toward said object.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-09-23 | 1995-03-25 | 1995-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-09-23 | 1999-03-25 | 1999-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-09-23 | 2003-03-25 | 2003-09-24 | $7700.00 | Window Closed / Lapsed |