Patent ID: 6396622
Filing Date: 2002-05-28
Classification: G02F

Abstract:
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.