Patent ID: 6034779
Filing Date: 2000-03-07
Classification: G01B

Abstract:
An array element examination method for detecting a position of an array element in which plural elements have optical axes substantially parallel with one another and are arranged in an array state so that the coordinate of the i-th element (where i=1 to N, N being the number of elements) in a plane perpendicular to said optical axes is represented by (Xo.sub.i, Yo.sub.i), comprising the steps of:providing a lense array in which plural lenses corresponding to said plural elements and having focal lengths f.sub.i equal to the substantially mutually parallel optical axes are arranged so that the coordinate of the optical axis of the i-th lens in the plane perpendicular to the optical axis of said each lens is represented by (X1.sub.i, Y1.sub.i) and an image forming lense having a focal length f.sub.2 for forming the image of the light from each lens of the lens array, when the lens array and the image forming lense form the image of each element within a plane of a detecting surface in the light receiving region of said optical detector which is perpendicular to the optical axes of the lenses constituting said lens array, arranging the lens array and the image forming lens relative to the plural elements so that relationships of the following expressions (1) to (3) are satisfied and fetching the light from the i-th element among said plural elements by the i-th lens in said lens array, and forming an image of the fetched light in a desired position (Xs.sub.i, Ys.sub.i) of said detecting surface by the image forming lens;detecting each element image formed by said image forming step, andobtaining the position of each element from the detection signal obtained by said step:Xo.sub.i -(k.times.X1.sub.i)=Xs.sub.i /M (1)Yo.sub.i -(k.times.Y1.sub.i)=Ys.sub.i /M (2).eta.={(k-1).times.(.beta.+.xi.)-1].times..beta./{.xi..times.(k-1)-1}(3)in whichk: a value which is obtained by dividing a distance between each element and a first principal point of the lens in the lens array corresponding to said each element of f.sub.1 ;.beta.: a value which is obtained by dividing the focal length f.sub.2 of the image forming lens by f.sub.1 ;.xi.: a value which is obtained by dividing a distance obtained by subtracting the focal lengths f.sub.1 and f.sub.2 from a distance between a second principal point of each lens of the lens array and a first principal point of the image forming lens by f.sub.1 ;.eta.: a value which is obtained by dividing a distance between a second principal point of the image forming lens and the detecting surface by f.sub.1 ;M: a magnification of an optical system constituted of the lens array and the image forming lens, represented by M=-.beta./{1+(1-k).times..xi.}; andX, Y axes: coordinate axes having directions perpendicular to an optical axis direction (Z-axis direction) of the lenses constituting the lens array and being orthogonal to each other, each coordinate of (Xo.sub.i, Yo.sub.i), (X1.sub.i, Yo.sub.i) and (Xs.sub.i, Ys.sub.i) being on the basis of the common X and Y coordinate axes.