Wide field of view infrared zoom lens assembly having a constant F/number
First Claim
1. An apparatus comprising an infrared lens system, said infrared lens system including:
- a collecting and focusing section and a diffracting section which cooperate to focus infrared radiation at an image plane;
said collecting and focusing section including a plurality of lens elements which are located along an optical axis in optical communication with each other, and which are each made of a material having an Abbe V-number which is less than 200 in each of first and second infrared wavebands that are different, said lens elements including first and second focusing zoom lenses which are supported for movement along the optical axis, and said lens elements further including first and second collecting lenses which are stationarily supported with respect to the optical axis; and
said diffracting section including a diffracting lens having thereon a diffractive surface, wherein said diffracting lens can be moved between a first location and a second location in which said diffractive lens is respectively located along the optical axis and spaced from the optical axis, and wherein when said diffracting lens is in the first location, said diffracting lens is in optical communication with said lens elements and said diffractive surface thereon corrects color aberrations in a selected one of the first and second wavebands.
2 Assignments
0 Petitions
Accused Products
Abstract
A wide field of view infrared zoom lens assembly (16) having a constant F/Number. The wide field of view infrared lens assembly (16) includes a focusing component (33), a collecting component (37), an aperture stop (46), and a diffracting component (41). The focusing component (33) may include a pair of focusing zoom lenses (34, 36). The collecting component (37) may include a first collecting lens (38) and a second collecting lens (40). The focusing component (33) and the collecting component (37) may be formed from high dispersion, low index material. The aperture stop (46) may be mounted to the first collecting lens (38) to maintain a constant F/Number. The diffracting component (41) may include a diffractive surface to correct color aberrations associated with an infrared waveband. The focusing component (33) and the collecting component (37) cooperate with the diffracting component (41) to focus infrared radiation at an image plane (15) of an infrared detector (18).
-
Citations
20 Claims
-
1. An apparatus comprising an infrared lens system, said infrared lens system including:
-
a collecting and focusing section and a diffracting section which cooperate to focus infrared radiation at an image plane;
said collecting and focusing section including a plurality of lens elements which are located along an optical axis in optical communication with each other, and which are each made of a material having an Abbe V-number which is less than 200 in each of first and second infrared wavebands that are different, said lens elements including first and second focusing zoom lenses which are supported for movement along the optical axis, and said lens elements further including first and second collecting lenses which are stationarily supported with respect to the optical axis; and
said diffracting section including a diffracting lens having thereon a diffractive surface, wherein said diffracting lens can be moved between a first location and a second location in which said diffractive lens is respectively located along the optical axis and spaced from the optical axis, and wherein when said diffracting lens is in the first location, said diffracting lens is in optical communication with said lens elements and said diffractive surface thereon corrects color aberrations in a selected one of the first and second wavebands. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
-
-
19. An apparatus comprising an infrared lens system, said infrared lens system including:
-
a collecting and focusing section and a diffracting section which cooperate to focus infrared radiation at an image plane;
said collecting and focusing section including a plurality of lens elements which are located along an optical axis in optical communication with each other, and which are each made of a material having similar optical characteristics in each of first and second infrared wavebands that are different, said lens elements including first and second focusing zoom lenses which are moveable along the optical axis, and said lens elements further including first and second collecting lenses which are stationarily supported with respect to the optical axis; and
said diffracting section including first and second diffracting lenses respectively having thereon a first diffractive surface and a second diffractive surface, wherein each said diffracting lens can be moved between an operational location and a nonoperational location in which that diffractive lens is respectively located along the optical axis and spaced from the optical axis, said second diffracting lens being in the nonoperational location thereof when said first diffracting lens is in the operational location thereof, and said first diffractive lens being in the nonoperational location thereof when said second diffracting lens is in the operational location thereof;
wherein when said first diffracting lens is in the operational location thereof, said first diffracting lens is in optical communication with said lens elements and said first diffractive surface thereon corrects color aberrations in the first waveband; and
wherein when said second diffracting lens is in the operational location thereof, said second diffracting lens is in optical communication with said lens elements and said second diffractive surface thereon corrects color aberrations in the second waveband.
-
-
20. An apparatus comprising an infrared lens system, said infrared lens system including a collecting and focusing section and a diffracting section which cooperate to focus infrared radiation at an image plane;
- said collecting and focusing section including a plurality of lens elements which are located along an optical axis in optical communication with each other, and which are each made of a material having an Abbe V-number which is less than 200 in each of a near infrared waveband and a far infrared waveband, said lens elements including first and second focusing zoom lenses which are moveable along the optical axis, and said lens elements further including first and second collecting lenses which are stationarily supported with respect to the optical axis;
said diffracting section including a diffracting lens which is removably supported in a position along the optical axis in optical communication with said lens elements, said diffracting lens being selected from the group consisting of;a diffracting lens having thereon a near infrared diffractive surface which cooperates with said lens elements to focus radiation in the near infrared waveband at the image plane, said near infrared diffractive surface correcting color aberrations in the near infrared waveband; and
a diffracting lens having thereon a far infrared diffractive surface which cooperates with said lens elements to focus radiation in the far infrared waveband at the image plane, said far infrared diffractive surface correcting color aberrations in the far infrared waveband.
- said collecting and focusing section including a plurality of lens elements which are located along an optical axis in optical communication with each other, and which are each made of a material having an Abbe V-number which is less than 200 in each of a near infrared waveband and a far infrared waveband, said lens elements including first and second focusing zoom lenses which are moveable along the optical axis, and said lens elements further including first and second collecting lenses which are stationarily supported with respect to the optical axis;
Specification