William T Plummer

US Patent:

6595427, Jul 22, 2003

Filed:

Aug 31, 2000

Appl. No.:

09/652427

Inventors:

Vivek K. Soni - Lynnfield MA
J. Barry Mahoney - Andover MA
William T. Plummer - Concord MA
Richard G. Egan - Dover MA

Assignee:

Polaroid Corporation - Waltham MA

International Classification:

G06K 1906

US Classification:

235491, 235468

Abstract:

The present invention relates to encoding and decoding of information using materials that are capable of mildly absorbing radiation over a wide range of infrared wavelengths and substantially non-absorbing in the visible wavelengths. Examples of such encoding of information are bar codes and area markings. Information is encoded in markings on a base medium by depositing or intertexturing on the base medium a material where the surface dimensions, thickness and presence of the material contain the encoded information. The encoding, as disclosed in this invention, utilizes a lower cost, more stable material than a material that is capable of highly absorbing over a range of infrared wavelengths and substantially non-absorbing in the visible wavelengths. However, since the material used in this invention is mildly absorbing in the infrared range, the signal obtained by reflecting or transmitting infrared radiation from the markings will be less distinct. Thus, inventive methods are needed to ensure that the encoded information can be decoded.

US Patent:

6643390, Nov 4, 2003

Filed:

Apr 19, 2000

Appl. No.:

09/553468

Inventors:

Peter P. Clark - Boxborough MA
Douglas S. Goodman - Sudbury MA
William T. Plummer - Concord MA

Assignee:

Polaroid Corporation - Waltham MA

International Classification:

G06K 900

US Classification:

382124, 356 71

Abstract:

A compact, low-cost finger imager, to be used for enrolling and recognizing individuals based upon their finger ridge patterns. The optical system employs viewing beyond the critical angle and darkfield illumination for maximum image contrast. The optical system is afocal and telecentric, achieving corrected distortion with oblique viewing.

US Patent:

6786416, Sep 7, 2004

Filed:

May 27, 2003

Appl. No.:

10/445592

Inventors:

Vivek K. Soni - Lynnfield MA
J. Barry Mahoney - Andover MA
William T. Plummer - Concord MA
Richard G. Egan - Dover MA

Assignee:

Polaroid Corporation - Waltham MA

International Classification:

G06K 1906

US Classification:

235491

Abstract:

The present invention relates to encoding and decoding of information using materials that are mildly absorbing radiation over a wide range of infrared wavelengths and substantially non-absorbing in the visible wavelengths. Examples of such encoding of information are bar codes and area markings. Information is encoded in markings on a base medium by depositing or intertexturing on the base medium a material where the surface dimensions, thickness and presence of the material contain the encoded information. The encoding utilizes a lower cost, more stable material than a material that is highly absorbing over a range of infrared wavelengths and substantially non-absorbing in the visible wavelengths. However, since the material is mildly absorbing in the infrared range, the signal obtained by reflecting or transmitting infrared radiation from the markings will be less distinct. Thus, inventive methods are needed to ensure that the encoded information can be decoded.

US Patent:

6994257, Feb 7, 2006

Filed:

May 27, 2003

Appl. No.:

10/445594

Inventors:

Vivek K. Soni - Lynnfield MA, US
J. Barry Mahoney - Andover MA, US
William T. Plummer - Concord MA, US
Richard G. Egan - Dover MA, US

Assignee:

Polaroid Corporation - Waltham MA

International Classification:

G06K 7/10

US Classification:

235468

Abstract:

The present invention relates to encoding and decoding of information using materials that are capable of mildly absorbing radiation over a wide range of infrared wavelengths and substantially non-absorbing in the visible wavelengths. Examples of such encoding of information are bar codes and area markings. Information is encoded in markings on a base medium by depositing or intertexturing on the base medium a material where the surface dimensions, thickness and presence of the material contain the encoded information. The encoding, as disclosed in this invention, utilizes a lower cost, more stable material than a material that is capable of highly absorbing over a range of infrared wavelengths and substantially non-absorbing in the visible wavelengths. However, since the material used in this invention is mildly absorbing in the infrared range, the signal obtained by reflecting or transmitting infrared radiation from the markings will be less distinct. Thus, inventive methods are needed to ensure that the encoded information can be decoded.

US Patent:

7426020, Sep 16, 2008

Filed:

Aug 1, 2005

Appl. No.:

11/193324

Inventors:

William T. Plummer - Concord MA, US
George W. McClurg - Jensen Beach FL, US
John F. Carver - Palm City FL, US

Assignee:

Cross Match Technologies, Inc. - Palm Beach Gardens FL

International Classification:

G06K 9/74

US Classification:

356 71, 356446

Abstract:

A directionally-oriented reflective device is optically coupled to a prism surface in a skin ridge pattern imaging system to reflect illumination light at relatively small angles, along an optical path to an imaging device, so that minimal light is lost from the optical system. Examples of such directionally-oriented reflective devices include, but are not limited to, echelon reflectors, faceted reflective surfaces, retroreflectors, aluminum paint, nacreous pigment, and slightly rough mirror surfaces.

US Patent:

7591557, Sep 22, 2009

Filed:

Apr 25, 2006

Appl. No.:

11/410776

Inventors:

William T. Plummer - Concord MA, US

Assignee:

WTP Optics, Inc. - Concord MA

International Classification:

G02C 7/02
B29D 11/00
G02B 1/12

US Classification:

351177, 264 132, 264 137

Abstract:

A solid state, compression method for fabricating lenses, lens blanks, and lens components from materials ground into fine powders having mechanical properties the make them capable of being formed into cohesive monolithic masses that are low in scattering. The fine powders may be admixtures of host matrix materials and others which, when combined, provide preferred optical properties such as index and dispersion. Parts possessing transmission from within the range from the ultraviolet to the infrared are possible. The method is particularly suited to low temperature formation of aspheric lenses transmissive in the near and far IR.

US Patent:

7926942, Apr 19, 2011

Filed:

Aug 13, 2009

Appl. No.:

12/540575

Inventors:

William T. Plummer - Concord MA, US

Assignee:

WTP Optics, Inc. - Concord MA

International Classification:

G02C 7/02
B29D 11/00

US Classification:

351177, 264 11, 264 132

Abstract:

Solid state lenses, lens blanks, and lens components comprising compressible materials ground into fine powders having mechanical properties that make them capable of being formed into cohesive monolithic masses that are low in scattering. The fine powders may be admixtures of host matrix materials and others which, when combined, provide preferred optical properties such as index and dispersion. Parts possessing transmission from within the range from the ultraviolet to the infrared are possible. The materials are suited to low temperature formation of aspheric lenses transmissive in the near and far IR.

US Patent:

7959286, Jun 14, 2011

Filed:

Aug 13, 2009

Appl. No.:

12/540591

Inventors:

William T. Plummer - Concord MA, US

Assignee:

WTP Optics, Inc. - Concord MA

International Classification:

G02C 7/02
B29D 11/00

US Classification:

351177, 264 11

Abstract:

Solid state lenses, lens blanks, and lens components formed of compressible mixed powders of two or more optical substances where the mixing ratio has been deliberately varied from place to place within the volume of the optical component to produce optically useful variations in the local refractive. The compressible mixed powders are ground as fine powders having mechanical properties that make them capable of being formed into cohesive monolithic masses that are low in scattering. The fine powders may be admixtures of host matrix materials and others which, when combined, provide preferred optical properties such as index and dispersion. Parts possessing transmission from within the range from the ultraviolet to the infrared are possible. The materials are suited to low temperature formation of aspheric lenses transmissive in the near and far IR.