Patent ID: 8000017
Filing Date: 2011-08-16
Classification: G02B,Y10S

Abstract:
1. A manufacturing method for a lens array apparatus including a lens array that includes a plurality of lenses formed such as to be arrayed in a predetermined array direction and formed to have a predetermined thickness in a thickness direction that is perpendicular to the array direction, that emits light that has entered the plurality of lenses and corresponds to each lens from each lens towards a predetermined converging point, and a light-emitting device that is disposed in a position facing the lens array in the thickness direction and on which a plurality of light-emitting elements of a same number as a number of lenses are formed, the light-emitting elements respectively emitting light corresponding to each lens towards the plurality of lenses, the manufacturing method wherein: as a predetermined angle of gradient in relation to the thickness direction for each lens, an exiting direction of light from each of the plurality of lenses is at an angle of gradient allowing a converging point of the light emitted from each lens to be positioned on a predetermined straight line that corresponds to each lens and is parallel in the thickness direction, under a plurality of different ambient temperatures, each center axis of the plurality of lenses is formed parallel with the thickness direction, and the exiting direction is at the angle of gradient by the plurality of light-emitting elements being formed such as to be displaced by a predetermined displacement amount in the array direction from each center axis of the plurality of lenses, from a coefficient of temperature dependence of refractive index and coefficient of linear expansion of a material forming the lens array, an amount of change in the thickness direction of a position of each converging point of the plurality of lenses accompanying a predetermined temperature change and an amount of change in a distance of each center axis of the plurality of lenses from a reference surface of the lens array accompanying the predetermined temperature change are determined, the reference surface being perpendicular to the array direction, for each of the plurality of lenses, a right triangle is utilized comprising a first side that is parallel with the thickness direction and has a length equivalent to the amount of change in the position of the converging point and a second side that is parallel with the array direction and has a length equivalent to the amount of change in the distance of the center axis, and an angle formed by a hypotenuse of the right triangle and the thickness direction is determined for each lens, a displacement amount is determined for each of the plurality of light-emitting elements corresponding to each lens, the displacement amount allowing an exiting direction of the light from each of the plurality of lenses to be at the angle determined for each lens in relation to the thickness direction, towards a direction in the array direction counter to a heat expansion direction of the lens array, and each light-emitting element is disposed such as to be displaced by the determined displacement amount.