Other

Alps Electric Co., Ltd.

Shigeru Yamaguchi

Hiroshi Wakuda

Masao Ohkita

Takayuki Sugawara

Kenji Uehara

Tomoo Fujioka

The present invention provides a cylindrical slab type gas laser for generating an excellent laser beam having substantially Gaussian intensity distribution of the focussed output laser beam. For this end, a pair of cylindrical electrodesof different diameter are disposed vertically and concentrically. And laser medium is filled in the gap between the two cylindrical electrodesto define a cylindrical straight slab. Disposed at one end of the cylindrical top of the cylindrical straight slabis a ring-shaped trick mirror Mand also disposed at the center of the one end of the cylindrical straight slabis an output mirror Mto pass a part of the light and to reflect a part of the remaining light. On the other hand, disposed at the other end of the cylindrical straight slabis a w-axicon mirror M. The above construction eliminates the need for spacers between the two cylindrical electrodeswhich are required in a conventional gas laser.

Cylindrical straight slab type gas laser

The radius range of a formatted zone in each medium differs. A floppy disk and an another-standard high-capacity medium are distinguished by reading a reproduction output at an inside position in the formatted zone by heads. Since the another-standard high-capacity medium has a formatted zone starting from a more inside position than that for the floppy disk, both media can be distinguished by reading a reproduction output by the heads to check a difference in the inside position of the formatted zone.

Medium distinguishing method of a disk used in a disk drive

A bearing structure for a stepping motor including a stepping motor, a screw shaft integrated with the stepping motor, and a bearing member formed of a molding resin material for supporting a distal end of the screw shaft, wherein a cone-shaped recess is formed in the distal end of the screw shaft, and a dome-shaped projection to be in abutment with the recess is formed on the bearing member.

Growing community of inventors

Fukushima-ken, Japan

Shigeru Yamaguchi