Abstract: A spectrometer is incorporated to a conventional lensometer. The spectrometer includes a uniform extended light source including a light source having visible and ultraviolet emission and an extending integrating sphere including ultraviolet transmission. In the preferred embodiment, an Ebert spectrometer is utilized, although other spectrometers may be used as well. Light is emitted from the light source through the spectacle lens to be tested to a spherical reflecting surface. Upon reflection, the light is incident to a grating, retro reflected to the spherical surface and thereafter reflected for incidence to a charge coupled device for analysis of the generated spectrum. The system is provided with a slit and a field stop dimensioned so that through all ranges of lenses expected to be tested within designated tolerances of sphere, cylinder and prism, the spectrometer sees only and always a portion of the uniform extended light source.
Abstract: A perimeter is disclosed in which the projection surface of the bowl includes a hemispherical section bounded by a cylindrical perimeter to impart to the interior projection surface of the instrument a "bullet shaped" profile. The perimeter of preferred dimension includes a reduced diameter hemisphere occupying the central 45.degree. of solid angle from the fixated patient's eye. The cylindrical perimeter is joined to the hemisphere and is generated about a cylindrical axis commencing at the spherical center of the hemisphere and extending outward normally from the hemisphere to the point of patient eye placement. The diameter of the cylinder matches and forms a projection continuum with the radius of the hemisphere.
Type:
Grant
Filed:
March 20, 1992
Date of Patent:
June 21, 1994
Assignee:
Humphrey Instruments Incorporated
Inventors:
Charles E. Campbell, Vincent M. Patella
Abstract: A method for use with an eye examination instrument for automatically aligning the eye under examination with the instrument optical axis. An operator initially aligns the instrument optical axis manually with the eye under examination. A first adjustment to the initial alignment is then automatically made in the optical train of the instrument so as to laterally align the eye under examination. The size of the lateral adjustment is determined, and an axial adjustment of the optical train is automatically effected by an amount controlled by the size of the lateral adjustment so as to axially align the eye under examination, whereby the requisite axial adjustment is determined directly from the accomplished lateral adjustment without the need for intervention of the operator.
Abstract: In combination with a lens meter for measuring along a single optical path the power of suspect optics, an apparatus for positioning nose bridge mounted spectacles is disclosed. At least one nose locator piece simulating the shape and location of the human nose is mounted for sliding movement on a bar. A bar locks vertical lens movement on the base of the lens frame at the bottom of the lenses to establish the elevation of the visual center on each lens for each eye. The transverse spacing of the nose locator piece locates the remaining coordinate of the visual center of the suspect lens. The nose locator piece, when registered to the spectacles at the nose bridge, is read through an attached and typically magnified scale to indicate nose bridge to visual center distance. By using paired nose locator pieces and paired scales, rapid measurement of nose frame mounted spectacles can occur at the spaced visual centers for the right and left eye lens to a lens meter having a monocular light path.
Type:
Grant
Filed:
June 13, 1977
Date of Patent:
July 4, 1978
Assignee:
Humphrey Instruments Incorporated
Inventors:
Charles E. Campbell, William E. Humphrey