To obtain a microlens base plate whose light condensing efficiency is not spoiled and which has fine pitch by successively laminating at least plural concave microlenses made of transparent low-refractive index material, a transparent resin layer having a higher refractive index than the microlens, a transparent thin plate and a transference electrode layer on either side of a transparent base plate.
This microlens base plate 22 is constituted of the transparent base plate 33, the concave microlens 32, the transparent resin layer 31, the transparent thin plate 30 and the transference electrode layer 28. It is necessary to use the material having sufficient adhesive strength enough to stick the microlens 32 and the thin plate 30, heat resistance and light transmissivity and having the higher refractive index than that of the transparent low- refractive index material being the material of the microlens 32 as the material of the layer 31. The larger a difference between the refractive index of the transparent low-refractive index material being the material of the microlens 32 and that of the material of the layer 31 is, the shorter the focal distance of the microlens is, whereby the light condensing efficiency is improved.
ISHIMATSU TADASHI
KOGA OSAMU
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