Abstract: A vision tester comprises a slide projector for projecting a visual indication chart onto a curved display screen via a mirror rotated by a motor. The center of curvature of the curved display screen substantially coincides with the subject's eye. The rotation of the mirror causes an image of the visual indicator to be moved across the screen in a specific direction. When the subject provides a response to the moving image, the speed of image movement at the time of the response is detected and stored in a memory. The average of a plurality of such measurements is used to determine the subject's dynamic visual acuity.

Abstract: A mounting structure of plastic glass in the watch case enabling the mounting with a minimum amount of necessary deflection of the glass for preventing the crack of the glass. The glass has a radially extending projection in the lower portion of the periphery thereof and the watch case has a recess which has a radially extending groove which is adapted to engage the projection of the glass. The recess is provided with a beveled guiding portion at the entrance edge thereof and the projection has a beveled guiding portion at the leading edge thereof. The glass may be inserted into the recess of the case with the projection sliding on the beveled guiding edge of the recess.

Abstract: A dial and movement fixing structure comprising a ring having legs that are held between a case ring of a watch case and a back cover, and a dial attached to the ring, wherein projections formed on the ring are introduced into a plurality of notched portions formed in the periphery of the dial such that the dial is fixed to the ring.

Abstract: A case for a wristwatch, which comprises a shell fabricated from an outer thin metal plate, an annular metallic reinforcing member positioned within said shell, and an inner shell composed of an injection molded synthetic resin, said inner shell lying in intimate contact with an inner surface of said shell and having an inwardly facing annular recess into which said annular reinforcing member is fitted.