Abstract: Provided is an optical film that can eliminate rainbow unevenness when viewed with the naked eyes and provide favorable color tone uniformity when viewed at an oblique angle. This optical film has a low-refractive index layer on a plastic film, the plastic film has a slow axis that is an axis with the largest refractive index in a plane, and a fast axis that is an axis orthogonal to the slow axis in the plane of the plastic film, and the low-refractive index layer is located on the surface of the optical film. Linearly polarized light is incident, under predetermined conditions, from a surface on a side opposite to the low-refractive index layer of the optical film, and transmitted light of the linearly polarized light is used to measure the a* value and b* value of the L*a*b* color system at 11 measurement points with different angles.

Abstract: The present disclosure addresses the problem of providing an optical plastic film such that rainbow unevenness when viewed with naked eyes and blackout when viewed with polarized sunglasses can be suppressed without any axis alignment or increase in the in-plane phase difference.

Abstract: A spherical binocular capable of being conveniently portable and suitable for use for watching a game in a baseball stadium, a soccer ground or the like. Two hemispherical shells are foldably or pivotally connected together into a spherical configuration. The hemispherical shells each are formed at a center thereof with an ocular through-hole, in which an ocular concave lens is fitted. A front plate is fitted in a front opening edge of each of the shells and formed at a center thereof with an objective opening, in which an objective convex lens is arranged so as to be aligned with the objective convex lens. When the hemispherical shells are folded over each other to align the front opening edges with each other, a holding pawl and holding groove of one of the hemispherical shells are fittedly engaged with a holding groove and a holding pawl of the other of the hemispherical shells, respectively.