Abstract: An object of the present invention is to provide a dental polishing instrument that causes no clogging, that prevents occurrence of any secondary flaw, that is excellent in the polishing property, and that can provide high gloss in a short time period, for a dental prosthetic appliance difficult to polish. Another object thereof is to provide a dental polishing instrument that enables easy discharge of polishing sludge while that simultaneously shows sufficient strength. A dental polishing instrument according to the present invention can suppress clogging and occurrence of any secondary flaw due to the polishing sludge and can efficiently polish by forming a polishing abrasive grain layer including polishing abrasive grains and a resin material, into protrusions on the surface of a base material thereof and by disposing the protrusions on the base material.

Abstract: An object of the present invention is to provide a dental polishing instrument that causes no clogging, that prevents occurrence of any secondary flaw, that is excellent in the polishing property, and that can provide high gloss in a short time period, for a dental prosthetic appliance difficult to polish. Another object thereof is to provide a dental polishing instrument that enables easy discharge of polishing sludge while that simultaneously shows sufficient strength. A dental polishing instrument according to the present invention can suppress clogging and occurrence of any secondary flaw due to the polishing sludge and can efficiently polish by forming a polishing abrasive grain layer including polishing abrasive grains and a resin material, into protrusions on the surface of a base material thereof and by disposing the protrusions on the base material.

Abstract: An optical disc recording/reproduction device is provided, in which a tracking drive offset amount (21) is given to a tracking drive signal (19), a beam spot position irradiated on a photo-detector (7) is shifted by a servo controller (18), and a CPU (16) detects a divided wobble signal balance being data-recorded. The CPU (16) causes a memory (17) to store the tracking drive offset amounts at which the wobble signal balance is uniform according to the wobble signal balance and the tracking drive offset amount. Further, the CPU (16) controls the beam spot position by adding the tracking drive offset amount read out from the memory (17) to the tracking drive signal (19) when performing recording or reproducing to/from the optical disc.

Abstract: There is provided an optical disc recording/reproduction device in which a tracking drive offset amount (21) is given to a tracking drive signal (19), a beam spot position irradiated on a photo-detector (7) is shifted by a servo controller (18), and by using an optical disc on which pits are recorded or not recorded, a CPU (16) detects some or all of the divided wobble signal balance, a lens error signal, a wobble jitter value, and an AYIP read error count. The CPU (16) causes a memory (17) to store at least one of the tracking drive offset amounts at which the wobble signal balance is uniform, the lens error signal reference voltage and wobble jitter value are minimum, and the AYIP read error count as well as the respective tracking drive offset amounts. Furthermore, the CPU (16) controls the beam spot position by adding the tracking drive offset amount read out from the memory (17) to the tracking drive signal (19) when performing recording or reproducing to/from the optical disc.

Abstract: An optical disc recording/reproducing apparatus capable of performing a stable reading of address information. A signal generating circuit for detecting a wobble signal based on a meander of the recording area of an optical disc, comprising a lowpass filter (LPF) (15) for passing therethrough only those lower parts of the frequencies of signals from a light receiving element of an optical pickup which are near a wobble signal band, or a bandpass filter (BPF) (16) for passing therethrough only those frequencies of the signals from the light receiving element which are within a predetermined range of a wobble signal frequency band, wherein the LPF (15) or BPF (16) is used to eliminate the affect of record pulses superimposed on the signals from the light receiving element, thereby reducing address information acquisition errors due to the affection of noise and hence obtaining a stable recording operation.

Abstract: An optical disc recording/reproducing apparatus is provided which can obtain the best recording quality. Data is recorded while tracking is displaced by gradually supplying an offset voltage (deviation value) to a tracking error signal, and then reproduction is performed on a recording area. The jitter value (reading state of address information) of biphase data generated from a reproduction RF signal is detected by a biphase jitter detector (20). Further, on the basis of the offset voltage value (tracking deviation) supplied to the tracking error signal and the detected jitter value of the biphase data, a CPU (14) determines an offset voltage value where the biphase data has the minimum jitter value, as a tracking deviation for obtaining the best reading state of data, and records the offset voltage value in memory (15).