The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 25, 1986
Filed:
May. 18, 1982
Masao Nohda, Yokosuka, JP;
Nippon Kogaku K.K., Tokyo, JP;
Abstract
A method of measuring the radius of curvature of an object to be examined has a first procedure of projecting two pairs of light spots onto the object from different directions, a second procedure of obtaining by an imaging optical system the reflected images of the two pairs of light spots reflected by the object, and a third procedure of measuring the radius of curvature of the object from the positional relation between the reflected images by the imaging optical system. An apparatus for carrying out this method includes measuring optical means having an objective lens, first projection optical means for projecting a pair of light spots onto an object to be examined from a direction symmetric to the optical axis of the objective lens, second projection optical means for projecting a pair of light spots onto the object from a direction symmetric to the optical axis of the objective lens and discrete from the first projection optical system, photoelectric converting means for producing signals corresponding to at least three projection spacings in which the spacing between the images of each of said pairs of light spots has been projected in two predetermined directions at a predetermined position on the optical axis of the measuring optical system and in a plane orthogonal to said optical axis, and operation display means for determining and displaying the directions of the principal meridians of the object and the radii of curvature in those directions from said at least three projection spacings measured by the apparatus.