Robert E Ramsey

US Patent:

20220252916, Aug 11, 2022

Filed:

Mar 1, 2022

Appl. No.:

17/683673

Inventors:

- Beverly Hills CA, US
Robert A. Ramsey - Boulder CO, US
Graham J. Woodgate - Henley-on-Thames, GB
Jonathan Harrold - Leamington Spa, GB
Michael G. Robinson - Boulder CO, US

International Classification:

G02F 1/13
G02F 1/01
F21V 8/00

Abstract:

A display apparatus comprises at least one spatial light modulator and at least one curved view angle control element that comprises plural retarders arranged between the display polariser of each spatial light modulator, and an additional polariser. The curvature of the view angle control element provides increased luminance uniformity for a head-on user and increased visual security to an off-axis snooper.

US Patent:

20220214574, Jul 7, 2022

Filed:

Jan 19, 2022

Appl. No.:

17/579037

Inventors:

- Beverly Hills CA, US
Robert A. Ramsey - Boulder CO, US
Graham J. Woodgate - Henley-on-Thames, GB

International Classification:

G02F 1/13363
G02F 1/1335
G02F 1/13357

Abstract:

A privacy display comprises a polarised output spatial light modulator, reflective polariser, plural polar control retarders and a polariser. A birefringent surface relief diffuser structure is arranged to transmit light from the display with high transparency and provide diffuse reflection of ambient light to head-on display users. In a privacy mode of operation, on-axis light from the spatial light modulator is directed without loss and with low diffusion, whereas off-axis light has reduced luminance and increased diffusion. Further, overall display reflectivity is reduced for on-axis reflections of ambient light, while reflectivity is increased for off-axis light. The visibility of the display to off-axis snoopers is reduced by means of luminance reduction, increased frontal reflectivity and diffusion of ambient light. In a public mode of operation, the liquid crystal retardance is adjusted so that off-axis luminance and reflectivity are unmodified.

US Patent:

20230125159, Apr 27, 2023

Filed:

Aug 11, 2022

Appl. No.:

17/886233

Inventors:

- Beverly Hills CA, US
Graham J. Woodgate - Henley-on-Thames, GB
Robert A. Ramsey - Boulder CO, US
Jonathan Harrold - Leamington Spa, GB

International Classification:

G02F 1/13363
G02B 5/30
G02F 1/1335
G02F 1/137
G02F 1/13
G02F 1/1337
G02F 1/1347
F21V 8/00

Abstract:

A privacy display comprises a spatial light modulator and a compensated switchable liquid crystal retarder arranged between first and second polarisers arranged in series with the spatial light modulator. In a privacy mode of operation, on-axis light from the spatial light modulator is directed without loss, whereas off-axis light has reduced luminance. The visibility of the display to off-axis snoopers is reduced by means of luminance reduction over a wide polar field. In a wide angle mode of operation, the switchable liquid crystal retardance is adjusted so that off-axis luminance is substantially unmodified.

US Patent:

20230116008, Apr 13, 2023

Filed:

Oct 13, 2022

Appl. No.:

17/965344

Inventors:

- Beverly Hills CA, US
Graham J. Woodgate - Henley-on-Thames, GB
Michael G. Robinson - Boulder CO, US
Robert A. Ramsey - Boulder CO, US
Ben Ihas - Boulder CO, US

International Classification:

G02F 1/13
G02F 1/1335
G02F 1/1337

Abstract:

A switchable privacy display comprises a spatial light modulator with output polariser, a reflective polariser, a polar control liquid crystal retarder and an additional polariser. The electrodes of the polar control liquid crystal retarder are patterned with a mark. In wide angle and narrow angle operational modes, the electrodes of the liquid crystal retarder are driven such that the mark is not visible. In a mark display state, the electrodes are driven to provide visibility of the mark in reflected light to an off-axis observer.

US Patent:

20230099000, Mar 30, 2023

Filed:

Sep 27, 2022

Appl. No.:

17/954225

Inventors:

- Beverly Hills CA, US
Graham J. Woodgate - Henley-on-Thames, GB
Michael G. Robinson - Boulder CO, US
Robert A. Ramsey - Boulder CO, US
Ben Ihas - Boulder CO, US

International Classification:

G02F 1/13
G09G 3/36
G09G 3/34
G02F 1/1343
G02F 1/01
G02F 1/1335

Abstract:

A switchable privacy display comprises a spatial light modulator with output polariser, a reflective polariser, a polar control liquid crystal retarder and an additional polariser. The electrodes of the polar control liquid crystal retarder are patterned with a mark. In wide angle and narrow angle operational modes, the electrodes of the liquid crystal retarder are driven such that the mark is not visible. In a mark display state, the electrodes are driven to provide visibility of the mark in reflected light to an off-axis observer.

US Patent:

20230014072, Jan 19, 2023

Filed:

Apr 28, 2022

Appl. No.:

17/731384

Inventors:

- Beverly Hills CA, US
Graham J. Woodgate - Henley-on-Thames, GB
Robert A. Ramsey - Boulder CO, US
Jonathan Harrold - Leamington Spa, GB

International Classification:

G02F 1/1335
G02F 1/13363
F21V 8/00
B60K 35/00

Abstract:

A privacy display comprises a spatial light modulator and a passive retarder arranged between first and second polarisers arranged in series with the spatial light modulator, On-axis light from the spatial light modulator is directed without loss, and off-axis light has reduced luminance. The visibility of the display to off-axis snoopers is reduced by means of luminance reduction over a wide polar field of view. Off-axis visibility of the display in an automotive vehicle can be reduced.

US Patent:

20210405403, Dec 30, 2021

Filed:

Jul 9, 2021

Appl. No.:

17/372059

Inventors:

- Beverly Hills CA, US
Graham J. Woodgate - Henley on Thames, GB
Robert Ramsey - Boulder CO, US

International Classification:

G02F 1/137
G02F 1/13363
G02F 1/13
G02F 1/1333
G02F 1/1335
F21V 8/00
G02F 1/1337
G02F 1/1343
G02F 1/139

Abstract:

A display comprises a polarised output spatial light modulator, switchable liquid crystal retarder, absorbing polarizer and touch panel electrodes. The switchable liquid crystal layer is stabilised by a cured reactive mesogen material during application of an applied voltage. Light scatter in privacy mode is reduced and visual security level enhanced. Visibility of disclinations during application of applied pressure, for example from a finger on a touch screen is minimised.

US Patent:

20210364839, Nov 25, 2021

Filed:

May 7, 2021

Appl. No.:

17/314854

Inventors:

- Boulder CO, US
Robert A. Ramsey - Boulder CO, US
Graham J. Woodgate - Henley-on-Thames, GB

International Classification:

G02F 1/13363
G02F 1/1335
G02F 1/13357

Abstract:

A privacy display comprises a polarised output spatial light modulator, reflective polariser, plural polar control retarders and a polariser. A birefringent surface relief diffuser structure is arranged to transmit light from the display with high transparency and provide diffuse reflection of ambient light to head-on display users. In a privacy mode of operation, on-axis light from the spatial light modulator is directed without loss and with low diffusion, whereas off-axis light has reduced luminance and increased diffusion. Further, overall display reflectivity is reduced for on-axis reflections of ambient light, while reflectivity is increased for off-axis light. The visibility of the display to off-axis snoopers is reduced by means of luminance reduction, increased frontal reflectivity and diffusion of ambient light. In a public mode of operation, the liquid crystal retardance is adjusted so that off-axis luminance and reflectivity are unmodified.