Abstract: An optical pickup is disclosed which is capable of recording or reproducing information from optical disks having different recording densities and includes a first optical unit having a light source which emits rays having a first wavelength for DVDs and a first light sensor which detects reflected rays, a second optical unit having a light source which emits rays having a second wavelength for CDs and a second light sensor which detects reflected rays, a beam splitter which directs the rays having the first wavelength and the rays having the second wavelength along substantially the same optical axis, and directs reflected rays from an optical disk to the first light sensor and the second light sensor, and an objective lens which has a numerical aperture (NA) of 0.6 or more, a focal length of 2.5 mm or less, an effective diameter of incidence of 3.0 mm or less and a working distance of 1.2 mm or less. The light pickup as a whole has a thickness of 7.

Abstract: An optical pickup for recording on and reproduction from recording media of different recording densities (e.g. a high density disk such as a DVD and a lower density disk such as an ordinary CD), and having a compact, thin and low power-consumption design. The optical pickup includes an objective lens, a first optical unit having a light-emitting element and a light-receiving element which are used for recording on and reproduction from the high-density optical disk, a second optical unit having a light-emitting element and a light-receiving element which are used for recording on and reproduction from the low-density optical disk, a beam splitter for guiding optical axes of the first and second optical units to the same optical axis, and a wavelength filter for changing a diameter of light beams incident on the objective lens between at the time of recording and reproduction for the high-density optical disk and at the time of recording and reproduction for the low-density optical disk.

Abstract: An object of the present invention is to provide an optical disk reproducing method and apparatus which allows for influence on focus servo control and tracking servo control involved in outputting voice information. The optical disk reproducing apparatus includes an optical pickup, a tracking servo control for causing the optical pickup to trace a track on the optical disk, a focus servo control and a pair of speakers for outputting reproduced voice information to the outside. When an information determining unit determines that the reproduced information includes voice information, the tracking servo control and the focus servo control are operated so as to provide a servo characteristic suitable for reproduction of voice information by the speakers to thereby reproduce information in the optical disk.

Abstract: A dot printer is adapted to make test printing by driving dot pins (161 to 167) included in a print head (16) before the first character is printed out. More specifically, a central processing unit (1) makes evaluation of the value of a period of approximately one-third of the period required for depression of a printing sheet by the dot pins, thereby to provide the same to an input/output port (6), before print control data for printing the first character is outputted. The input/output port is responsive to the output from the central processing unit to provide a printer driver (9) with a print timing signal of the pulse width of approximately one-third of the pulse width of the print timing signal required for printing the characters. The print driver is responsive to the applied print timing signal to drive the dot pins.