| 摘要 |
PURPOSE:To eliminate indistinctiveness from projected image, by composing a compensation filter board of a visible-light-permeable substance and making its entire thickness and refractive index constant. CONSTITUTION:An indent 9 of a radiation compensation filter layer 8, which is composed of a radiation-absorptive-visible-light-permeable substance in such a manner that its thickness is changed in accordance with compensation pattern of radiation corresponding to shape of an object to which radiation is applied, is filled with a substance, which has a similar refractive index to that of the radiation-absorptive- visible-light-permeable substance constituting the filter layer, by mold-injecting method, etc. to form a refractive index compensating layer 10. It is possible, by doing so, to maintain a constant thickness of a compensation filter board 5, which is formed by adjusting nonuniform surface of the compensation filter layer 8, and also to compensate for the refractive index. |
