Variable spot size illuminators with enhanced homogeneity and parfocality
First Claim
1. A variable spot size illuminator, comprising a) a first optical system for generating a homogeneous distribution of a selected radiation on an intermediate plane, b) a variable aperture disposed in said intermediate plane for selecting a portion of said homogenous distribution of radiation, and c) an objective optical system substantially fixedly positioned relative to said intermediate plane and optically coupled thereto so as to generate an image of said selected portion onto an illumination plane.
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Accused Products
Abstract
The present invention provides both continuously variable spot size illuminators and discretely variable spot size illuminators that can be utilized in many applications, e.g., photo-dynamic therapy, to provide a light spot on a treatment plane, e.g., a patient'"'"'s retina, whose size can be continuously or discretely adjusted while ensuring that the light fluence and the working focal distance remain substantially constant at all spot sizes, thereby preserving parfocality with other optical systems. In a continuous variable spot size illuminator of the invention, a focusing lens system is employed to form an image of a light source on an intermediate plane, and a variable aperture is utilized to select a portion of the intermediate image. An objective lens system then images the selected portion of the intermediate image onto a treatment plane. A discrete variable spot size illuminator of the invention employs a plurality of light shaping diffusers each imparting a pre-defined far field intensity distribution to light transmitted therethrough to select the shape and/or size of an image formed on a treatment plane from among a discrete number of choices, each associated with coupling one of the diffuser with a light source.
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Citations
37 Claims
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1. A variable spot size illuminator, comprising
a) a first optical system for generating a homogeneous distribution of a selected radiation on an intermediate plane, b) a variable aperture disposed in said intermediate plane for selecting a portion of said homogenous distribution of radiation, and c) an objective optical system substantially fixedly positioned relative to said intermediate plane and optically coupled thereto so as to generate an image of said selected portion onto an illumination plane.
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31. A discretely variable spot size illuminator, comprising
a) a radiation source, b) a plurality of light shaping diffusers each having a pre-defined optical relief to impart a selected far field intensity profile to light transmitted therethrough, c) a positioning device coupled to said diffusers to selectively coupling any of said diffusers to said light source for receiving light, and d) an objective lens disposed between the diffuser selected for coupling to the light source and a treatment plane to image the light transmitted through the diffuser onto the treatment plane, said image having the far field intensity profile corresponding to said selected diffuser.
Specification