Abstract: A digital signal processor (DSP) comprises a condition flag register directly accessible by the control microcomputer. Referring to a condition flag of the condition flag register every sampling period of the DSP, the DSP can change the content of a process every sampling period in accordance with the set status of the condition flag. The DSP sets the condition flag in the condition flag register at the beginning of a sampling period of the DSP by a set instruction, and resets the condition flag at the end of a sampling period by a reset instruction. The DSP may be modified to automatically reset the condition flag at the end of the sampling period in which the condition flag has been set.

Abstract: An optical disk in which a pattern such as a character that can be recognized is displayed in an information recording area by display pits or grooves formed between recording tracks constructed by pit trains indicative of information signals. An apparatus for manufacturing the optical disk in which information and display modulation light beams obtained by modulating a light beam in accordance with pattern signals for information and display, respectively, are separated from each other in the disk radial direction and are simultaneously irradiated to a resist layer formed on a recording surface of a disk.

Abstract: An optical disk having both recording surfaces on which are formed pits trains. A recognizable display pattern is formed by a group of dummy pits formed on one of the recording surfaces. An apparatus for manufacturing the optical disk in which a light beam is modulated in accordance with a dummy forming signal obtained by selectively stopping a dummy pulse, and the modulated light beam is irradiated to a resist layer formed on a recording surface of a disk to form a group of dummy pits representing a display pattern.

Abstract: A master optical disk recording apparatus forms a train of pits on a recording layer of a master optical disk by a laser beam which is emitted from the laser light source and is modulated by an acousto-optic modulator. An objective lens in the recording apparatus consists of a finite conjugate type lens and a convergence point on the acousto-optic modulation element where the laser beam is converged by a convergence lens is positioned outside of the focal point of the objective lens at the incidence side thereof.

Abstract: An optical disc is provided with: a disc substrate of light transmissive type having an information record surface including an information recorded region, where pits or grooves carrying an information signal are coaxially or spirally formed, and an information not-recorded region, where the pits or grooves carrying the information signal are not formed; a light reflective layer wholly disposed on the information record surface in the information recorded region, and partially disposed on the information record surface in the information not-recorded region such that an indication pattern is formed of the partially disposed light reflective layer on the information record surface in the information not-recorded region; and a protection layer disposed on the light reflective layer and a portion of the information record surface in the information not-recorded region where the light reflective layer is not disposed.

Abstract: A recording disk carrying a compressed video signal at a high recording density and a recorded information reproducing apparatus for reproducing the information recorded on the particular recording disk. A linear velocity of the reading of information is adjusted according to a data quantity signal reproduced from the recording disk having data areas in which a compressed video signal produced by the compression and coding process is recorded in predetermined unit blocks (GOP block) and at least a data quantity information recording area in which a data quantity signal representing the quantity of each unit of the compressed video signal is recorded.

Abstract: This optical disk is two-substrates bonding type. In the optical disk, from the first transparent substrate side toward the second substrate side, at least following layers are laminated in that order; (1) the first transparent substrate, (2) the first optical film, (3) the intermediate layer, (4) the second optical film, and (5) the second substrate. The intermediate layer is formed of a dry photohardenable film of light transmissive type, which has a viscosity of 3,500 to 400,000 poises at a room temperature and in a non-hardened condition and has a thickness of 5 to 200 .mu.m in the non-hardened condition. The shapes of pits or grooves and the extent of light transmissive property are set so that both of the first pit-groove surface on the first transparent substrate and the second pit-groove surface on the second substrate can be read by irradiating the optical disk with the beam for reproduction from the first transparent substrate side of the optical disk.

Abstract: A compressed picture information recording apparatus which sequentially stores modulated compressed video signals in a memory, and reads information from the memory in such a way as to reduce the information reading speed when the remaining memory space becomes smaller than a predetermined value and to increase the information reading speed when the remaining memory space becomes greater than the predetermined value. This apparatus records the read information on a recording disk at a recording linear velocity according to the information reading speed. This structure permits compressed video signals excluding invalid data to be continuously recorded on the recording disk at a variable transfer rate according to the producing rate of the compressed video signals, thus ensuring a high recording efficiency.

Abstract: A digital time base corrector in which a memory for correction of a time base is commonly used as a memory for correction of a drop-out and a signal process to a video signal which is replaced by a drop-out compensation is made unnecessary. The corrector has an image memory having a capacity to store the digital video signal by only two horizontal scan periods. When a drop-out occurs in the reproduction video signal, the writing operation into the image memory is inhibited. In the portion in which the drop-out occurred, the video data before about 2 H is read out in place of such a portion and the drop-out compensation is executed. Therefore, the drop-out portion is replaced by the video data of the same phase.

Abstract: A real-time image compression processor records on a CD or other recording media a compressed video signal which is compressively processed in a high recording efficiency at real-time as being reproduced by a VTR while preventing the image quality from being degraded. There are provided a first encoder for compressively encoding the video signal, and a second encoder for compressively encoding the signal obtainable by delaying such video signal for a given period of time. A parameter adjustment is executed for the second encoder in accordance with the compressed video signal obtained through the compressive encoding by the first encoder. The compressed video signal obtained by the second encoder is recorded on a recording medium.

Abstract: An optical reproducing system has a first optical path from a light source to an optical disc, and a second optical path from the optical disc to a photodetector. An objective lens is provided in the first optical path for forming an a non-collimated beam applied to the optical disc. A profile conversion filter having an angle dependent transmittance characteristic is provided between the objective lens and the optical disc.

Abstract: A digital time base corrector uses a memory with a reduced storage capacity, to reduce the cost. Absolute value data of an amplitude and polarity data of a burst signal in a color video signal are written into a memory every horizontal scan period. A signal in which a sync signal interval, a pedestal level interval, and a burst signal interval in the color video signal are eliminated is written as image data into the memory. The absolute value data, polarity data, and image data are read out from the memory. Burst signal data is reproduced on the basis of the absolute value data and polarity data. By inserting the burst signal data, sync signal data, and pedestal level data into the image data, a color video signal is reproduced.

Abstract: A digital time base corrector, when using a memory whose storage capacity is reduced to a value of about 1H of the video signal, can maintain an interleave relation between a luminance signal and a color signal of a video signal even when the writing operation into a memory is delayed by a jitter included in the demodulated video signal. When the read address is advanced from the write address in each of an image data memory and a subcarrier phase memory in one horizontal scan period, a discrepancy occurs between the polarity data read out from the subcarrier phase memory and the proper polarity data held in latch means. When such a discrepancy is detected, the color phase of the read-out image data is inverted. In starting the data reading operation for a new horizontal scan period, if it is detected that the operating mode has not shifted to the data writing operation for the new horizontal scan period, the color phase of the read-out image data is inverted for the new horizontal scan period.

Abstract: A digital time base corrector which can perfectly eliminate residual errors. A sync clock signal whose phase is synchronized with a time base fluctuation included in a reproduction video signal is formed in accordance with at least one of the horizontal sync signal and the color burst signal which are separated from a reproduction video signal. The sync clock signal is phase-modulated in accordance with a burst error signal indicative of the time base fluctuation of the color burst signal in a period of time other than the generating period of time of at least the color burst signal in the reproduction video signal, thereby obtaining a write clock signal of the image memory.

Abstract: An optical pickup for emitting a laser beam is provided for reading data recorded on an optical disc. The axis of the laser beam is tilted at a skew angle from a perpendicular line to the surface of the disc. Error rate in reproduced data read out by the pickup is determined, and an inferior disc having a rare error rate is eliminated.

Abstract: A digital time base corrector reduces the capacity of a memory to approximately a 1 H of image data while maintains the interleave relationship between a luminance signal and a chrominance signal of a video signal. Polarity data indicating the polarity of a burst signal is generated every 1 H, and a latch circuit is provided for holding and outputting the polarity data during a period of reading image data and polarity data from an image data memory and a sub-carrier phase memory, corresponding to the 1 H in which the polarity data was generated. When dropout occurs in a video signal, the image data and the polarity data are inhibited from being written into the image data memory and the sub-carrier phase memory. When discrepancy is detected between read polarity data and polarity data held in the latch circuit, the color phase of the read image data is inverted.

Abstract: An optical information recording medium recordable of the analogue NTSC color video signal under the conditions of a high S/N ratio and a low jitter, and capable of being played by a commercially available LD player. The medium comprises: a transparent substrate on which pre-grooves are formed with a depth of 1450-2050 angstroms; an optical absorbing layer with an absorbance of 0.7-0.

Abstract: A disc-shaped record medium provided with an information recording area including tracks for recording information therein, which information recording area is divided into a plurality of circular recording areas in the radial direction thereof. Each of the circular recording areas includes at least a first block wherein individual track pitches are gradually reduced in accordance with the radial distance from the center portion of the record medium. Also, a second block may be provided following the first block, in which track pitches are gradually increased in proportion to the radial distance from the center portion of the record medium. With the disc-shaped record medium constructed as such, not only can the recording capacity thereof as a whole be increased, but smooth shifting of the head for an information recording or reproducing operation is also obtained.

Abstract: The object of the present invention is to provide a an optical recording medium provided with a reflective film having a high reflectivity and durability and a means for producing thereof, and it can be obtained by a method comprising the steps of: first placing on a heating object an aluminum metal alloy containing at least one of 0.05-0.2 wt.% metal selected from the group of iron, copper and silicon, and also having 0.7-3.0 wt.% manganese; and evaporating the aluminum metal alloy in a vacuum by means of a vapor deposition process to an information signal recorded surface of a transparent synthetic resin plate. In other words, an optical recording medium according to the present invention is provided with a light reflective film covering an information signal recorded surface of a transparent synthetic resin plate, wherein the light reflective film is formed in a vacuum by means of a vapor deposition process of an aluminum metal alloy containing at least one of 0.05-0.2 wt.

Abstract: A digital signal processing device for outputting a holding data in an output register from a DSP in synchronism with a second clock pulse having a frequency lower than that of a first clock pulse for conducting arithmetic processing in the DSP. Accordingly, data to be output from the DSP can be directly read by a microcomputer, and contents in a coefficient memory and a delay time memory, for example, can be updated in accordance with the read data. Further, the digital signal processing device can be applied to an audio apparatus such as a loudness controller and a spectrum indicating apparatus.