KENNETH M SMITH, MD
Urology in Saint Paul, MN

5946134, Aug 31, 1999

Sep 22, 1997

8/935247

Gerald M. Benson - Woodbury MN
Kenneth L. Smith - White Bear Lake MN
John C. Kelliher - Oakdale MN
Mark E. Gardiner - Santa Rosa CA

Minnesota Mining & Manufacturing Company - St. Paul MN

G02B 5122, G02B 5124

359529

A cube corner article and method of manufacturing the article from a series of directly machinable unitary substrates. The method of manufacture comprises the first step of providing an initial unitary directly machinable substrate of material suitable for forming retroreflective surfaces. Then, a first cube corner element array zone is formed having a plurality of geometric structures including cube corner elements. The zone is created by directly machining at least two sets of parallel grooves in the substrate. A replica of the cube corner element array zone is formed as an additional unitary substrate suitable for forming retroreflective surfaces. Portions of the replica substrate material are removed. The removal of these portions forms at least two intersecting cavities bounded by side walls in the replica at a depth at least that of the cube corner elements formed by the groove sets. Each cavity comprises at least one side wall which extends to a depth into the replica substantially equal to the deepest depth of any other intersecting cavity.

2013014, Jun 13, 2013

Feb 7, 2013

13/761518

Kenneth L. SMITH - White Bear Lake MN, US

3M INNOVATIVE PROPERTIES COMPANY - ST. PAUL MN

G02B 5/124, B32B 3/30

359530, 428161

Structured surface articles such as molds or sheeting are formed on a compound substrate including a machined substrate and a replicated substrate. In one embodiment, the structured surface is a cube corner element on a compound substrate. In another embodiment, the structured surface is a geometric structure that has a plurality of faces, where one face is located on the machined substrate and another face is located on the replicated substrate. In yet another embodiment, at least some of the faces include a compound face with a portion formed on the machined substrate and a portion formed on the replicated substrate. The method of making a structured surface article including a geometric structure having a plurality of faces includes forming an array of geometric structures in a first surface of a machined substrate; passivating selected locations of the first surface of the machined substrate; forming a replicated substrate of the machined substrate to form a compound substrate; forming an array of second geometric structures on a second surface opposite the first surface on the machined substrate; and removing selected portions from the second surface of the machined substrate.

6318987, Nov 20, 2001

Aug 9, 2000

9/636520

Dan E. Luttrell - Corning NY
Robert L. Erwin - Rohnert Park CA
Kenneth L. Smith - White Bear Lake MN
Gerald M. Benson - Woodbury MN

3M Innovative Properties Company - St. Paul MN

B41B 1154, B29D 1100

425193

Laminae suitable for use in molds for forming retroreflective cube corner elements and methods for making such laminae are disclosed. A representative lamina includes a first row of cube corner elements disposed in a first orientation and a second row of optically opposing cube corner elements disposed. The working surface of a lamina is provided with a plurality of cube corner elements formed by the optical surfaces defined by three groove sets. Opposing first and second groove sets are formed in the working surface of a lamina. The first groove set forms a plurality of structures having first and second optical surfaces disposed in mutually perpendicular planes that intersect along a reference edge. The second groove set forms a corresponding plurality of structures on the opposite side of the lamina. A third groove is formed in the working surface of the lamina along an axis substantially perpendicular to the axes of the grooves of the first and second groove sets.

6257860, Jul 10, 2001

Aug 10, 2000

9/636730

Dan E. Luttrell - Corning NY
Robert L. Erwin - Rohnert Park CA
Kenneth L. Smith - White Bear Lake MN
Gerald M. Benson - Woodbury MN

3M Innovative Properties Company - St. Paul MN

B41B 1154, B29D 1100

425193

Laminae suitable for use in molds for forming retroreflective cube corner elements and methods for making such laminae are disclosed. A representative lamina includes a first row of cube corner elements disposed in a first orientation and a second row of optically opposing cube corner elements disposed. The working surface of a lamina is provided with a plurality of cube corner elements formed by the optical surfaces defined by three groove sets. Opposing first and second groove sets are formed in the working surface of a lamina. The first groove set forms a plurality of structures having first and second optical surfaces disposed in mutually perpendicular planes that intersect along a reference edge. The second groove set forms a corresponding plurality of structures on the opposite side of the lamina. A third groove is formed in the working surface of the lamina along an axis substantially perpendicular to the axes of the grooves of the first and second groove sets.

6287670, Sep 11, 2001

Jan 11, 1999

9/227963

Gerald M. Benson - Woodbury MN
Kenneth L. Smith - White Bear Lake MN
James C. Coderre - Lake Elmo MN

3M Innovative Properties Company - St. Paul MN

B32B 300, G02B 5122

428172

Retroreflective sheeting includes a body layer having a structured surface with recessed faces and top surfaces, the recessed faces forming cube corner cavities. The recessed faces have a high specular reflectivity, while the top surfaces have a low specular reflectivity. In some embodiments a substantially continuous film of reflective material covers the structured surface, and a masking substance is provided over the reflective material at the top surfaces. Alternatively, the top surfaces are given a non-smooth surface finish so that the film of reflective material on those portions has a diffuse reflectivity. In other embodiments the film of reflective material is discontinuous, disposed selectively on the recessed faces and not on the top surfaces. A cover layer is also provided, and can bond at least to the top surfaces. Keeping the top surfaces substantially free of reflective material inhibits corrosion and can enhance the bond integrity.

6302992, Oct 16, 2001

Sep 7, 2000

9/656697

Kenneth L. Smith - White Bear Lake MN
Gerald M. Benson - Woodbury MN

3M Innovative Properties Company - St. Paul MN

B32B 3100, B29D 1100

156268

A method is disclosed for manufacturing a plurality of laminae for use in a mold suitable for use in forming retroreflective cube corner articles. Each lamina has opposing first and second major surfaces defining therebetween a first reference plane. Each lamina further includes a working surface connecting the first and second major surfaces. The working surface defines a second reference plane substantially parallel to the working surface and perpendicular to the first reference plane and a third reference plane perpendicular to the first reference plane. The method includes (a) orienting a plurality of laminae to have their respective first reference planes parallel to each other and disposed at a first angle relative to a fixed reference axis, (b) forming a plurality of cube corner elements on the working surfaces of the plurality of the laminae, wherein the plurality of cube corner elements have three approximately mutually perpendicular lateral faces that mutually intersect to define a cube corner element peak, and (c) removing a plurality of laminae from the assembly to alter the configuration of the mold surface.

5831767, Nov 3, 1998

Jun 6, 1996

8/660785

Gerald M. Benson - Woodbury MN
Kenneth L. Smith - White Bear Lake MN

Minnesota Mining and Manufacturing Company - St. Paul MN

G02B 5122, G02B 5124

359529

A cube corner article has a plurality of geometric structures formed by at least three intersecting groove sets. Each geometric structure has three faces arranged as a cube corner element. Some of the geometric structures also have a fourth face which is not a part of a cube corner element. At least one of the grooves in the three intersecting groove sets has a first and second side surface extending uniformly from a groove vertex, the first side surface forming one of the three faces and the second side surface forming the fourth face.

5564870, Oct 15, 1996

Oct 20, 1994

8/326588

Gerald M. Benson - Woodbury MN
Kenneth L. Smith - White Bear Lake MN

Minnesota Mining and Manufacturing Company - St. Paul MN

B23C 328, B23C 502

409131

A method is disclosed for manufacturing a cube corner article comprising the steps of providing a machinable substrate material suitable for forming reflective surfaces, and creating a plurality of geometric structures including cube corner elements in the substrate. The step of creating the cube corner elements comprises directly machining at least three sets of parallel grooves in the substrate so that only one side of at least one groove in at least one groove set forms cube corner element optical surfaces.

5926314, Jul 20, 1999

Jul 17, 1998

9/118350

Kenneth L. Smith - White Bear Lake MN
Gerald M. Benson - Woodbury MN

Minnesota Mining and Manufacturing Company - St. Paul MN

G02B 5124

359530

The present invention provides improved cube corner retroreflective articles which exhibit a wide range of retroreflective entrance angularity in at least one plane, and preferably in two or more planes. An article in accordance with the present invention includes a structured surface having at least one array of cube corner elements formed by three intersecting sets of substantially parallel grooves. Each cube corner element includes a base triangle bonded by one groove from each of the three intersecting groove sets, the base triangle being scalene.