OPTICAL PRISM, MANUFACTURING METHOD OF OPTICAL PRISM, CEMENTED PRISM, VIDEO DISPLAY APPARATUS, HEAD MOUNTED DISPLAY, AND VIDEO IMAGING APPARATUS

摘要

PROBLEM TO BE SOLVED: To mold an ocular prism 22 to an almost symmetrical shape about a reference surface S by devising a position of a gate 31 and thereby to realize high molding precision. SOLUTION: The gate 31 which becomes an entrance when a resin is poured into a metal mold is provided at any ridgeline part intersecting the reference surface S crossing respective surfaces described above among ridgeline parts of respective surfaces of the ocular prism 22: an incidence surface (a surface 22a), a reflection surface (a surface 22e) and an ejection surface (a surface 22b). The resin is poured into the metal mold via the gate 31 and then the resin is cured. By pouring the resin into the metal mold via the gate 31 thus located, the resin can be equally poured into both sides toward a reference surface S and thereby the ocular prism 22 having an almost symmetrical whole shape about the reference surface S can be obtained by using a corresponding metal mold. COPYRIGHT: (C)2008,JPO&INPIT