| 摘要 |
<p>A prism unit comprises a prism having at least one optical surface in its inside, and a prism base disposing the prism. The prism base includes at least three seating surfaces that are attached to a surface orthogonal to the optical surface of the prism, and a seating surface bonded part that is bonded to the prism by an adhesive. A groove is formed between the seating surface and the seating surface bonded part.</p> |
