Optics: eye examining – vision testing and correcting – Eye examining or testing instrument – Objective type
Reexamination Certificate
2007-10-16
2007-10-16
Mai, Huy (Department: 2873)
Optics: eye examining, vision testing and correcting
Eye examining or testing instrument
Objective type
C351S206000, C351S211000
Reexamination Certificate
active
11389241
ABSTRACT:
An optometry apparatus comprising: a target projecting optical system adapted for diopter movement, for projecting a target onto a fundus of an examinee's eye to form an image of the target on the fundus, wherein the target projecting optical system including: an objective lens to be positioned at the front of the examinee's eye: a relay lens arranged so that a front focal point of the relay lens coincides with an approximate conjugate point of an anterior segment of the examinee's eye with respect to the objective lens positioned at the front of the examinee's eye; a plus-power lens arranged at the approximate conjugate point of the anterior segment with respect to the positioned objective lens, the plus-power lens having refractive power determined so that a front focal point of the plus-power lens coincides with an approximate conjugate point of the fundus with respect to the positioned objective lens; and an astigmatism correction optical element arranged between the relay lens and the plus-power lens, for correcting astigmatism of the examinee's eye.
REFERENCES:
patent: 3880502 (1975-04-01), Humphrey
patent: 4679921 (1987-07-01), Yamada et al.
patent: 5309186 (1994-05-01), Mizuno
patent: 5483305 (1996-01-01), Kohayakawa et al.
patent: 2002/0047993 (2002-04-01), Takeuchi et al.
patent: A-1-129830 (1989-05-01), None
patent: A 02-213320 (1990-08-01), None
patent: A-11-70076 (1999-03-01), None
Mai Huy
Nidek Co. Ltd.
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