WIDE-APERTURE OBJECTIVE FOR SCANNING DEVICE Russian patent published in 2004 - IPC

FIELD: wide-aperture objective designed for operating in infrared spectrum range, possibly in scanners of low-size thermal-vision devices.

SUBSTANCE: wide-aperture objective for infrared spectrum range 3.0 -5.0 micrometers includes afocal adapter and focusing lens between which scanning member is arranged. Afocal adapter realized according to Galilean telescope and focusing lens are made of separate meniscus type lens. Afocal adapter has first positive meniscus turned by its convexity to object and second negative meniscus turned by its concavity to image and made of germanium. Focusing lens has first positive meniscus turned by convexity to object and second negative meniscus turned by concavity to object and made of fluorite. Material of positive lens satisfies to next conditions: , where -refraction indexes of material, respectively for = 4.0 micrometers, for = 3.0 micrometers, = 5.0 micrometers, - irradiation wave length. Objective provides improved quality of image, increased relative aperture up to 1 : K = 1 : 1.25 at angular field , increased rear apex portion and increased spacing between afocal adapter and focusing lens.

EFFECT: enhanced quality of image.

7 dwg