Abstract: In a spherical lens surface processing method, a lens surface is ground to a spherical surface by forming a contact state in which a rotating cup-shaped grinding stone is placed in contact with the lens surface and a sphere center oscillation state in which the cup-shaped grinding stone oscillates along the lens surface centered on a sphere center. In the sphere center oscillation state, the distance from the center of the sphere center oscillation to the contact point of the cup-shaped grinding stone with the lens surface is set to be the same as the radius of the spherical surface. The oscillation width of the sphere center oscillation is set so that the contact point of the cup-shaped grinding store with the lens surface can move from one peripheral edge of the lens surface past the lens center on the lens surface to the other peripheral edge.
Abstract: In a spherical lens surface processing method, a lens surface is ground to a spherical surface by forming a contact state in which a rotating cup-shaped grinding stone is placed in contact with the lens surface and a sphere center oscillation state in which the cup-shaped grinding stone oscillates along the lens surface centered on a sphere center. In the sphere center oscillation state, the distance from the center of the sphere center oscillation to the contact point of the cup-shaped grinding stone with the lens surface is set to be the same as the radius of the spherical surface. The oscillation width of the sphere center oscillation is set so that the contact point of the cup-shaped grinding store with the lens surface can move from one peripheral edge of the lens surface past the lens center on the lens surface to the other peripheral edge.
Abstract: According to this lens-centering method, a state in which a lens is sandwiched at prescribed pressing force between a lens holder and a lens processing dish is brought about. Next, the lens-processing dish is rotated at slow speed about a rotation axis line that passes through the center and the spherical center of the lens-processing surface thereof, and is made to oscillate at a slight angle about the spherical center of the lens-processing surface as the center of oscillating action. The spherical center of a first lens spherical surface of the lens is guided to the spherical center of a lens-retaining surface of the lens holder, and the spherical center of a second lens spherical surface is guided to the spherical center of the lens-processing surface. A lens mounted in the spherical center-type processing machine can be set to an accurately centered state thereby.
Abstract: According to this lens-centering method, a state in which a lens is sandwiched at prescribed pressing force between a lens holder and a lens processing dish is brought about. Next, the lens-processing dish is rotated at slow speed about a rotation axis line that passes through the center and the spherical center of the lens-processing surface thereof, and is made to oscillate at a slight angle about the spherical center of the lens-processing surface as the center of oscillating action. The spherical center of a first lens spherical surface of the lens is guided to the spherical center of a lens-retaining surface of the lens holder, and the spherical center of a second lens spherical surface is guided to the spherical center of the lens-processing surface. A lens mounted in the spherical center-type processing machine can be set to an accurately centered state thereby.
Abstract: A spherical core type lens grinding device (1) performs an operation wherein a dish-shaped grindstone (8) provided with a spherical grindstone surface (8a) which is equipped with diamond abrasive grains, is pressed against a surface-to-be-ground (7a) of a lens blank (7) to be ground, and wherein the dish-shaped grindstone (8) is rotated and is simultaneously swung, resulting in said surface-to-be-ground (7a) being ground to a spherical surface. In an initial-stage grinding process, grinding is performed at first processing pressure and first rotational speed. In an intermediate-stage grinding process, grinding is performed at second processing pressure and second rotational speed. In a last-stage grinding process, grinding is performed at third processing pressure and third rotational speed. The second processing pressure is a pressure at which the spherical grindstone surface (8a) can bite into the lens blank (7).
Abstract: A lens processing device (1) is adapted such that a lens (11) is sucked and held by a lens holder (12) rotatably and rockably supported on the front end of a lens holder shaft (13) through a pivot bearing mechanism (14) and then such that a lens surface (11a) is processed by moving the lens (11) and a lens processing tool (31) relative to each other with the lens processing tool (31) pressed to the lens (11). The lens (11) can be moved along a desired trajectory on a vertical plane containing a Z-axis and an X-axis, which are perpendicular to each other, by controlling feeding of the lens holder (12) in the Z-axis and X-axis directions by means of a Z-axis movement mechanism (19) and an X-axis movement mechanism (15). Thus, the lens surface (11a) can be processed with the lens (11) horizontally pressed to a circular arc-shaped processing surface (31a) of the lens processing tool (31).