Abstract: A plate-like base of a substrate holder has an upper surface perpendicular to a central axis. A supporter is disposed circumferentially around the central part of the base and protrudes upward from the upper surface of the base to support the lower surface of a substrate. A flexible seal is disposed around the entire periphery of the supporter. An upper edge portion of the seal is located above the supporter. When the substrate holder adsorbs a substrate, gas present between the base and the substrate is sucked through a suction port with the upper edge portion of the seal being in contact with the lower surface of the substrate. This allows the substrate to approach the base and come in contact with the supporter while making the seal bend down. As a result, even if there is a warp in a substrate, the substrate can be held suitably.

Abstract: A plate-like base of a substrate holder has an upper surface perpendicular to a central axis. A supporter is disposed circumferentially around the central part of the base and protrudes upward from the upper surface of the base to support the lower surface of a substrate. A flexible seal is disposed around the entire periphery of the supporter. An upper edge portion of the seal is located above the supporter. When the substrate holder adsorbs a substrate, gas present between the base and the substrate is sucked through a suction port with the upper edge portion of the seal being in contact with the lower surface of the substrate. This allows the substrate to approach the base and come in contact with the supporter while making the seal bend down. As a result, even if there is a warp in a substrate, the substrate can be held suitably.

Abstract: In an optical filter apparatus in which a filter loading disk having a plurality of filters is rotated around a rotation axis so as to position a desired filter onto an optical axis of a color separation prism, the filter loading disk and the rotation axis are unitedly formed, while the rotation axis is supported by a housing member disposed in front of and behind the disk, thereby reducing the number of parts to decrease the manufacturing cost of the apparatus while preventing the disk from fluctuating upon rotation. In a filter disk (8), a disk holding section (8A) holding a plurality of filters (9) and an axis section (8B) are unitedly formed, thereby reducing the number of parts. The axis section (8B) is supported by an axial hole (1A) and an axial hole (4A) of a dust cover (4) so as to increase the fitting length of the axis section (8B), thereby preventing the filter disk (8) from fluctuating upon rotation.

Abstract: A lens mount for a TV camera for mounting a lens having a bayonet ring on its rear face and a cylindrical projection which is smaller in diameter than the bayonet ring and extends rearward coaxially with the optical axis of the lens is provided with a camera-side bayonet ring which is movable between an engagement position where the camera-side bayonet ring is engaged with the lens side bayonet ring to hold the lens on the camera and a disengagement position where the bayonet rings are disengaged from each other to permit removal of the lens from the camera.