| 摘要 |
PROBLEM TO BE SOLVED: To suppress the effect of reflected light by providing an optical control region contiguously to an element region having a part for entering an external light thereby controlling the entering light actively. SOLUTION: The surface type optical function element comprises an element region 11 having a pn junction and the like with light entering part and light leaving part being provided on one and the other major surfaces, respectively, and an optical control region 12 disposed contiguously to the element region 11. A plurality of function elements are arranged in multistage with the major surfaces extending in parallel with each other. The optical control region 12 reduces the reflected light thus reducing the quantity of reflected light to be fed back (feedback amount) Pret. The feedback amount Pret is determined from an interference effect Cint, a coupling efficiency Cc and a reflection intensity Pr according to formula I; Pret=Cint.Cc.Pr. The interference effect Cint is set by regulating the ratio of area between the element region 11 and optical control region 12, the intensities Pr1 , Pr2 of reflected light from the element region 11 and optical control region 12, and the like. |
