Electro-optic apparatus and process for multi-frequency variable refraction with minimized dispersion

• US 6,396,622 B1
• Filed: 09/18/2000
• Issued: 05/28/2002
• Est. Priority Date: 09/13/2000
• Status: Expired due to Fees

• Current Assignee: Ray M. Alden
• Original Assignee: Ray M. Alden
• Inventors: Alden, Ray M.
• Primary Examiner(s): Epps, Georgia
• Assistant Examiner(s): Spector, David N.
• Application Number:
  US09/665,191
• Time in Patent Office: 617 Days
• Field of Search: 359/315,316,319,494,495,496,497,669,670,720,721,722,742 349/57,196,198,200,74,75
• US Class Current: 359/315
• CPC Class Codes: G02F 1/133371 Cells with varying thickness of the liquid crystal layer
• CPC Class Codes: G02F 1/13471 in which all the liquid crystal cells or layers remain transparent, e.g. FLC, ECB, DAP, HAN, TN, STN, SBE-LC cells G02F1/13475 takes precedence
• CPC Class Codes: G02F 1/29 for the control of the position or the direction of light beams, i.e. deflection
• CPC Class Codes: G02F 1/291 Two-dimensional analogue deflection
• CPC Class Codes: G02F 1/294 Variable focal length devices
• CPC Class Codes: G02F 2203/28 focussing or defocussing

Abstract

The object of the prevent invention is to provide an optical system for producing variable refraction with minimized dispersion. A first material with a first apex angle in a first state and a second material with a second apex angle in a first state produce a first net refraction angle in at least two frequencies of electromagnetic radiation such that the beams that entered parallel exit parallel (to within a controllable tolerance). Said first material with said first apex angle in a second state and said second material with said second apex angle in a second state produce a second net refraction angle in at least two frequencies of electromagnetic radiation such that the beams that entered parallel exit parallel (to within a controllable tolerance).

Claims

1. An achromatic optical assembly comprising a plurality of refractive elements arranged along an optical axis, said plurality of elements including:

a first refractive element formed of a first electro-optic material operable in at least two refractive states, and having first and second refracting surfaces disposed in non-parallel planes through which at least two different wavelengths of electromagnetic radiation passes;

a second refractive element formed of a second electro-optic material operable in at least two refractive states, and having first and second refractive surfaces disposed in non-parallel planes through which at least two different wavelengths of electromagnetic radiation passes;

means to vary the refractive state of said first electro-optic material between said at least two refractive states, and means to vary the refractive state of said second electro-optic material between said at least two refractive states;

wherein, in a first condition, the refractive index of said first electro-optic material is in a first state and the refractive index of said second electro-optic material is in a first state, such that the rays of said electromagnetic radiation of at least two different wavelengths are brought to focus at a fist focal length in such a way that rays which are parallel when incident upon said first refracting surface of said first electro-optic material, remain parallel when exiting said second refracting surface of said second electro-optic material; and

wherein, in a second condition, the refractive index of said first electro-optic material is in a second state and the refractive index of said second electro-optic material is in a second state, such that rays of said electromagnetic radiation of at least two different wavelengths are brought to focus at a second focal length in such a way that rays which are parallel when incident upon said first refracting surface of said first electro-optic material, remain parallel when exiting said second refracting surface of said second electro-optic material.

2. The achromatic optical assembly of claim 1 wherein said first non-parallel plane in which said first surface of said first electro-optic material is disposed is part of a conic section which is formed by said first surface of said first electro-optic material, said conic section being symmetric about said axis.

3. The achromatic optical assembly of claim 2 wherein said first electro-optic material is arranged in a concentric array of structures each of said structures having a said first surface which forms a conic section symmetric about said axis.

4. The invention of claim 1 wherein said means to vary the refractive state of said first electro-optic material is a change of voltage.

5. The invention of claim 1 further comprising a means to monitor the temperature of at least one of said electro-optic materials.

6. The invention of claim 1 wherein at least one electro-optic material through which said electromagnetic radiation passes is a liquid crystal.

7. The invention of claim 1 further comprising a computer connected so as to send a signal to control the refractive state of at least one said electro-optic material.

8. An achromatic optical assembly comprising a plurality of refractive elements through which electromagnetic radiation passes in series, said plurality of elements including:

a first refractive element formed of a first electro-optic material operable in at least two refractive states, and having first and second refracting surfaces disposed in non-parallel planes through which at least two different wavelengths of electromagnetic radiation passes;

a second refractive element formed of a second electro-optic material operable in at least two refractive states, and having first and second refractive surfaces disposed in non-parallel planes through which at least two different wavelengths of electromagnetic radiation passes;

means to vary the refractive state of said first electro-optic material between said at least two refractive states, and means to vary the refractive state of said second electro-optic material between said at least two refractive states;

wherein, in a first condition, the refractive index of said first electro-optic material is in a first state and the refractive index of said second electro-optic material is in a first state, such that the rays of said electromagnetic radiation of at least two different wavelengths which are parallel when incident upon said first refracting surface of said first electro-optic material, remain parallel when exiting said second refracting surface of said second electro-optic material; and

wherein, in a second condition, the refractive index of said first electro-optic material is in a second state and the refractive index of said second electro-optic material is in a second state, such that rays of said electromagnetic radiation of at least two different wavelengths which are parallel when incident upon said first refracting surface of said first electro-optic material, remain parallel when exiting said second refracting surface of said second electro-optic material.

9. The invention of claim 8 wherein said means to vary the refractive state of said first electro-optic material is a change/of voltage.

10. The invention of claim 8 further comprising a means to monitor the temperature of at least one of said electro-optic materials.

11. The invention of claim 8 wherein at least one electro-optic material through which said electromagnetic radiation passes is a liquid crystal.

12. The invention of claim 8 further comprising a computer connected so as to send a signal to control the refractive state of at least one said electro-optic material.