Multi-pixel liquid crystal cell array

• US 7,046,326 B2
• Filed: 03/17/2003
• Issued: 05/16/2006
• Est. Priority Date: 02/21/2003
• Status: Expired due to Term

• Current Assignee: II-VI Delaware, Inc. (Coherent Corp.)
• Original Assignee: Xtellus Inc.
• Inventors: Cavanaugh, Shanti A., Young, Mark E., Molinari, Louis J., Austin, Lindsay W.
• Primary Examiner(s): Parker, Kenneth
• Assistant Examiner(s): CHUNG, DAVID Y
• Application Number:
  US10/391,510
• Publication Number:
  US 20040183988A1
• Time in Patent Office: 1,156 Days
• Field of Search: 349/155, 349/156, 349/153
• US Class Current: 349/155
• CPC Class Codes: G02F 1/093 used as non-reciprocal devices, e.g. optical isolators, circulators G02F1/0955 takes precedence
• CPC Class Codes: G02F 1/1326 Liquid crystal optical waveguides or liquid crystal cells specially adapted for gating or modulating between optical waveguides
• CPC Class Codes: G02F 1/133382 Heating or cooling of liquid crystal cells other than for activation, e.g. circuits or arrangements for temperature control, stabilisation or uniform distribution over the cell
• CPC Class Codes: G02F 1/133521 Interference filters
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: G02F 1/13355 Polarising beam splitters [PBS]
• CPC Class Codes: G02F 1/1339 Gaskets; Spacers; Sealing of cells
• CPC Class Codes: G02F 1/31 Digital deflection, i.e. optical switchingG02F1/33 takes precedence
• CPC Class Codes: G02F 2201/305 diffraction grating
• CPC Class Codes: G02F 2203/055 wavelength filtering
• CPC Class Codes: G02F 2203/06 Polarisation independent
• CPC Class Codes: G02F 2203/12 spatial light modulator

Abstract

A multi-pixel optical processing system includes a multi-pixel liquid crystal cell platform having a deposited metal gasket moisture barrier bonding two opposing substrates each having a spacer layer to accurately control cell gap thickness. A library of specialized pixel constructs is included that can be configured to yield predetermined optical functions at referential locations in the platform. A control system is provided utilizing a time division scheme that multiplexes temperature sensing and heating functions across an optional integrated active thermal element that may be integrated inside the liquid crystal platform. A calibration process characterizes the profile of the cell and generates a polynomial regression formula that provides the voltage drive output for all pixels in the platform based on the platform temperature and state of each pixel.

Claims

1. A multi-pixel liquid crystal cell platform, comprising:

A first substrate having a first electrode layer patterned with multiple pixels, and a first alignment layer,

a second substrate placed in opposition to the first substrate and having a second electrode and second alignment layer,

liquid crystals coupled between the first and second substrates,

a spacer element coupled between the first and second substrates,

A metal gasket element bonded to the first and second substrates,

wherein at least one pixel is a photovoltaic tap pixel.

2. A multi-pixel liquid crystal cell platform, comprising:

A first substrate having a first electrode layer patterned with multiple pixels, and a first alignment layer,

a second substrate placed in opposition to the first substrate and having a second electrode and second alignment layer,

liquid crystals coupled between the first and second substrates,

a spacer element coupled between the first and second substrates,

A metal gasket element bonded to the first and second substrates,

wherein at least one pixel is a polarization beam splitter/combiner pixel capable of functioning as a polarization independent variable optical attenuator.

3. A multi-pixel liquid crystal cell platform, comprising:

A first substrate having a first electrode layer patterned with multiple pixels, and a first alignment layer,

a second substrate placed in opposition to the first substrate and having a second electrode and second alignment layer,

liquid crystals coupled between the first and second substrates,

a spacer element coupled between the first and second substrates,

A metal gasket element bonded to the first and second substrates,

wherein at least one pixel is a Faraday rotator pixel capable of functioning as a polarization dependent variable optical attenuator with integrated isolator.

4. A multi-pixel liquid crystal cell platform, comprising:

A first substrate having a first electrode layer patterned with multiple pixels, and a first alignment layer,

a second substrate placed in opposition to the first substrate and having a second electrode and second alignment layer,

liquid crystals coupled between the first and second substrates,

a spacer element coupled between the first and second substrates,

A metal gasket element bonded to the first and second substrates,

wherein the first or second substrate further includes a sub wavelength optical element or nanostructure grating,

wherein the sub wavelength optical element is configured to operate in a capacity selected from the group consisting of polarization rotation, polarization filtration, beam splitting, polarization beam splitting, polarization beam combining, and waveguide.

5. A multi-pixel liquid crystal cell platform, comprising:

A first substrate having a first electrode layer patterned with multiple pixels, and a first alignment layer,

a second substrate placed in opposition to the first substrate and having a second electrode and second alignment layer,

liquid crystals coupled between the first and second substrates,

a spacer element coupled between the first and second substrates,

A metal gasket element bonded to the first and second substrates,

An active thermal element disposed between the first and second substrates,

further including a microcontroller that reads the temperature value of the cell and computes the temperature compensated voltage drive based on a stored regression profile of the cell operating characteristics across voltage.

6. A multi-pixel liquid crystal cell platform, comprising:

A first substrate having a first electrode layer patterned with multiple pixels, and a first alignment layer,

a second substrate placed in opposition to the first substrate and having a second electrode and second alignment layer,

liquid crystals coupled between the first and second substrates,

a spacer element coupled between the first and second substrates,

A metal gasket element bonded to the first and second substrates,

An active thermal element disposed between the first and second substrates, and

at least one VIA formed between the metal gasket element and first or second electrode.

7. A multi-pixel liquid crystal cell platform, comprising:

A first substrate having a first electrode layer patterned with multiple pixels, and a first alignment layer,

a second substrate placed in opposition to the first substrate and having a second electrode and second alignment layer,

liquid crystals coupled between the first and second substrates,

a spacer element coupled between the first and second substrates,

A metal gasket element bonded to the first and second substrates

An active thermal element disposed between the first and second substrates, and

at least one VIA formed between the active thermal element and the metal gasket element.