Dennis C Callahan

US Patent:

20210033943, Feb 4, 2021

Filed:

Oct 5, 2020

Appl. No.:

17/062960

Inventors:

- Cambridge MA, US
Steven J. Byrnes - Watertown MA, US
Juha-Pekka J. Laine - Boston MA, US
Gregg E. Favalora - Bedford MA, US
Joseph J. Register - Cambridge MA, US
Dennis M. Callahan - Natick MA, US
Michael G. Moebius - Allston MA, US

International Classification:

G02F 1/335
G02F 1/11
G03H 1/02
G03H 1/22
H03H 9/02

Abstract:

An electro-holographic light field generator device is disclosed. The light field generator device has an optical substrate with a waveguide face and an exit face. One or more surface acoustic wave (SAW) optical modulator devices are included within each light field generator device. The SAW devices each include a light input, a waveguide, and a SAW transducer, all configured for guided mode confinement of input light within the waveguide. A leaky mode deflection of a portion of the waveguided light, or diffractive light, impinges upon the exit face. Multiple output optics at the exit face are configured for developing from each of the output optics a radiated exit light from the diffracted light for at least one of the waveguides. An RF controller is configured to control the SAW devices to develop the radiated exit light as a three-dimensional output light field with horizontal parallax and compatible with observer vertical motion.

US Patent:

20190302569, Oct 3, 2019

Filed:

Mar 29, 2018

Appl. No.:

15/940079

Inventors:

- Cambridge MA, US
Michael G. Moebius - Somerville MA, US
Joy C. Perkinson - Cambridge MA, US
Dennis M. Callahan - Wellesley MA, US
Steven J. Byrnes - Watertown MA, US
Ian W. Frank - Arlington MA, US

International Classification:

G02F 1/335

Abstract:

There can be a problem of output intensity node or nodes as a function of angle, for waveguide-based optical modulators, such as leaky-mode surface acoustic wave modulators. Several approaches are illustrated that can be used to provide more uniform output light across a range of angles, i.e., that is avoid dark “drop-outs.” It can also be used to increase the output angle range or exit light fan. This is achieved by leveraging the different diffraction characteristics between different guided modes. It exploits the observation that utilizing different waveguide guided modes, e.g. TE0 like versus TE1-like, causes a SAW optical modulator to operate with different relationships between output angle and output intensity. It turns out that they can be at least complementary, that is: one waveguide mode can fill in the dark gaps of another wave guide mode.

US Patent:

20180284466, Oct 4, 2018

Filed:

Mar 28, 2018

Appl. No.:

15/938700

Inventors:

- Cambridge MA, US
Gregg E. Favalora - Bedford MA, US
Joseph J. Register - Cambridge MA, US
Steven J. Byrnes - Watertown MA, US
Ian W. Frank - Arlington MA, US
Dennis M. Callahan - Wellesley MA, US

International Classification:

G02B 27/22
G02F 1/335

Abstract:

Electro-holographic light field generator devices comprising surface acoustic wave (SAW) optical modulators are disclosed that employ multiple output couplers. These output couplers might be distributed along waveguides of the SAW modulators, within output coupling regions. Each of these output couplers can be configured for directing an incident leaky mode light at different output angles. In some cases, it may be desirable to employ the output couplers to function as different sub-pixels, to provide light to different viewing directions. The output couplers may be mirrors, volume gratings, chirped gratings, reflection gratings, two dimensional gratings, and/or transmission gratings. The output couplers may be angled so that the coupling output fans for each optical modulator are offset from the waveguide for that optical modulator.

US Patent:

20180284562, Oct 4, 2018

Filed:

Mar 28, 2018

Appl. No.:

15/938677

Inventors:

- Cambridge MA, US
Dennis M. Callahan - Wellesley MA, US
Michael G. Moebius - Somerville MA, US
Steven J. Byrnes - Watertown MA, US
Gregg E. Favalora - Bedford MA, US
Ian W. Frank - Arlington MA, US

International Classification:

G02F 1/335
G02B 27/22

Abstract:

An electro-holographic light field generator device comprises surface acoustic wave (SAW) optical modulators arranged in different directions. Specifically, some embodiments have SAW modulators arranged in pairs, nose-to-nose with each other, and have output couplers that provide face-fire light emission. These SAW modulators also possibly include SAW sense transducers and/or viscoelastic surface material to reduce crosstalk.

US Patent:

20180284563, Oct 4, 2018

Filed:

Mar 28, 2018

Appl. No.:

15/938684

Inventors:

- Cambridge MA, US
Dennis M. Callahan - Wellesley MA, US
Michael G. Moebius - Somerville MA, US
Steven J. Byrnes - Watertown MA, US
Gregg E. Favalora - Bedford MA, US
Ian W. Frank - Arlington MA, US

International Classification:

G02F 1/335
G02B 27/22

Abstract:

An electro-holographic light field generator device comprises surface acoustic wave (SAW) optical modulators arranged in different directions. Specifically, some embodiments have SAW modulators arranged in pairs, nose-to-nose with each other, and have output couplers that provide face-fire light emission. These SAW modulators also possibly include SAW sense transducers and/or viscoelastic surface material to reduce crosstalk.

US Patent:

20180217414, Aug 2, 2018

Filed:

Jan 30, 2018

Appl. No.:

15/883811

Inventors:

- Cambridge MA, US
Gregg E. Favalora - Bedford MA, US
Joseph J. Register - Cambridge MA, US
Ian W. Frank - Arlington MA, US
Dennis M. Callahan - Natick MA, US
Michael G. Moebius - Allston MA, US
Juha-Pekka J. Laine - Boston MA, US

International Classification:

G02F 1/11

Abstract:

An electro-holographic light field generator device is disclosed. The light field generator device has an optical substrate with a waveguide face and an exit face. One or more surface acoustic wave (SAW) optical modulator devices are included within each light field generator device. The SAW devices each include a light input, a waveguide, and a SAW transducer, all configured for guided mode confinement of input light within the waveguide. A leaky mode deflection of a portion of the waveguided light, or diffractive light, impinges upon the exit face. Multiple output optics at the exit face are configured for developing from each of the output optics a radiated exit light from the diffracted light for at least one of the waveguides. An RF controller is configured to control the SAW devices to develop the radiated exit light as a three-dimensional output light field with horizontal parallax and compatible with observer vertical motion.

US Patent:

20180217473, Aug 2, 2018

Filed:

Jan 30, 2018

Appl. No.:

15/883802

Inventors:

- Cambridge MA, US
Steven J. Byrnes - Watertown MA, US
Juha-Pekka J. Laine - Boston MA, US
Gregg E. Favalora - Bedford MA, US
Joseph J. Register - Cambridge MA, US
Dennis M. Callahan - Natick MA, US
Michael G. Moebius - Allston MA, US

International Classification:

G02F 1/335

Abstract:

An electro-holographic light field generator device is disclosed. The light field generator device has an optical substrate with a waveguide face and an exit face. One or more surface acoustic wave (SAW) optical modulator devices are included within each light field generator device. The SAW devices each include a light input, a waveguide, and a SAW transducer, all configured for guided mode confinement of input light within the waveguide. A leaky mode deflection of a portion of the waveguided light, or diffractive light, impinges upon the exit face. Multiple output optics at the exit face are configured for developing from each of the output optics a radiated exit light from the diffracted light for at least one of the waveguides. An RF controller is configured to control the SAW devices to develop the radiated exit light as a three-dimensional output light field with horizontal parallax and compatible with observer vertical motion.