In one embodiment, a self-describing fiducial includes a communication element that optically communicates navigation-aiding information. The navigation-aiding information may include a position of the self-describing fiducial with respect to one or more coordinate systems and the communication element communicates the navigation-aiding information to one or more navigating objects in the vicinity of the self-describing fiducial.

The present invention discloses a reflective holographic storage method and device, in which a reflection layer is plated on a back side of a holographic storage medium, and a new reference light is formed by utilizing the reflection layer, so that a phase conjugate reproduction light of a hologram is obtained. According to the invention, a recording device and a reading device can be provided on the same side of a medium, thereby obtaining a more compact system, reducing design difficulty, improving system stability, and improving the SNR (signal-noise ratio) of reproduction light by the interference between reproduction light and a conjugate reproduction light.

The present patent relates to a parallel reproducing holographic disk reading method and device, and belongs to the technical field of optical holographic storage. According to an angle-shift multiplexing method included in the present patent, multiplex recording is performed by simultaneously changing an incident angle of a reference light and moving a medium with a fixed angle change amount and a fixed shift amount. In this method, the reference light can be split for incidence, and then holograms in different units can be simultaneously reproduced. According to the method disclosed by the patent, a recorded hologram can be read and written in real time, and a recorded signal can be checked under a condition of satisfying a response time required by the medium.

A radial servo control device for a super-resolution optical disc includes an excitation light source, a servo light source, an integrated optical path, focusing units, a servo light detecting unit and a drive control unit; the drive control unit presets N detection error reference values with respect to each guide layer trench irradiated by servo light, and controls corresponding positions of the focusing units in N data tracks below each guide layer trench according to a comparison result between a detection result of servo reflected light and the detection error reference values. The device is applicable to a variety of super-resolution optical discs on the basis of stimulated radiation loss microscopy technology, a two-photon absorption technology, and the like, and achieves accurate radial servo control of super-resolution data tracks (<100 nm) without reducing the wavelength of servo light and the width of guide layer trenches.

A magnetic tape cartridge includes a case on which an identifier is displayed, and a storage medium in which reading condition information that is information regarding a condition for reading the identifier is stored.

The present invention relates to a holographic data storage device with a single-arm structure, and belongs to the technical field of optical holographic storage. According to the device disclosed in the present invention, a part of a reference arm and a part of a signal arm are integrated together to form a single-arm structure, which can not only reduce the number of optical and mechanical elements, but also reduce the system volume and cost without degrading performance. In addition, a signal beam and a reference beam share the same relay lens, so that the impact of environmental interference on the two beams is equal, and the stability of the entire system is improved.

A holographic multiplexed recording method for increasing storage capacity is disclosed. In a holographic recording and reproducing device, the moving direction of a storage medium is not coplanar with the plane where the optical axes of signal light and reference light are located, or the relative moving direction of the storage medium and the signal light or the reference light is not coplanar with the plane where the optical axes of the signal light and the reference light are located. Through the method, a certain angle exists between the grating vector direction and the moving direction or the relative moving direction, so that the phenomenon that the grating vector directions are the same does not occur when the medium is subjected to multiplexed recording after being rotated or flipped. Not only is multiplexing number increased, but also crosstalk caused by the same grating vector direction is prevented.

The present invention relates to a holographic storage device and method for simultaneously recording and reading on two sides, and pertains to the technical field of optical holographic storage. The device and method disclosed in the present invention use a characteristic that orthogonal light would not interfere with each other and a Bragg selectivity characteristic for holographic storage, and use two optical heads to constitute two interference fields orthogonal in polarization directions on two sides of a same position of a holographic storage medium, so as to perform two-path simultaneous recording and reading on a hologram. The device and method provided in the present invention implement two-path parallel recording and reading of holographic storage, and combine shift multiplexing and circumferential rotation multiplexing, thereby improving the speed of an information data recording and reading process while increasing a capacity of the holographic storage.

An optical encoder is provided. The encoder includes an optical disc mounted on a shaft, the optical disc containing pit and land markings; an optical pickup unit for an optical disc that receives light from the optical disc and supplies as an output an electrical signal representative of the received light, comprising: a reading head objective lens, and dynamic steering actuators that control the focus and tracking of the reading head objective lens; a processor that receives as an input the electrical signal from the optical pickup unit and reports motion of the substrate based on the received at least one electrical signal.

The present invention relates to the technical field of holographic multiplexing storage, and in particular, to a multiplexing method for increasing storage capacity in a disc-type holographic storage medium. According to the method disclosed by the present invention, holograms with different grating vector directions can be overwritten and recorded in the same storage medium according to Bragg selection characteristics of volume holographic records, and the obtained holograms do not affect each other. According to the method disclosed by the present invention, on the premise of ensuring low crosstalk between data pages, the multiplexing number of shift multiplexing storage is increased by using a cross-shift multiplexing method, and the storage density is improved.