A data writing and reading method is applied to a data storage system. The storage system includes a processor, a charged particle beam excitation modulation component, and a recording medium. The method is performed by the processor. The data writing method includes obtaining to-be-written data; controlling, based on the to-be-written data, the charged particle beam excitation modulation component to generate a charged particle beam array with a target modulation feature; and controlling the charged particle beams in the charged particle beam array to act on the recording medium to generate, in a target area of the recording medium, a target recording feature corresponding to the to-be-written data.

A multi charged particle beam writing method includes emitting each corresponding beam in an “on” state while starting and continuing tracking control, shifting a writing position by beam deflection of the multi beams, in addition to tracking control, while continuing tracking control, emitting each corresponding beam in the next “on” state to the next writing position having been shifted while continuing tracking control, and returning the tracking position by resetting tracking control, after emitting each next corresponding beam to the next writing position having been shifted at least once, wherein writing of a predetermined region is completed by repeating the number of preset times a group of performing emitting, shifting, emitting, and returning, wherein the tracking time from start to reset of tracking control in at least one of the repeated groups is longer than the others.

A method for optical transmission of a structure into a recording medium which can be transformed locally from a first undefined state into a second defined state by irradiating with photons from a photon source. The two states of the recording medium are manifested in different physical and/or chemical properties of the recording medium. At least one photon source having a photon flux of less than 10.sup.4 photons per second is selected for the irradiation with the photons. It was recognized that with such a low photon flux especially fine structures can advantageously be transmitted into the recording medium without the irradiation having to be partially blocked by a mask. In this manner, for a given wavelength (energy) of the photons, structures can be transmitted that are considerably smaller than the width, defined by the diffraction limit, of the probability distribution for the locations at which the emitted photons are incident.

Systems and methods for monitoring the status of air filters are provided. One or more thermoelectric sensors are provided to have an upstream sensing surface positioned adjacent the inlet surface of the air filter, and a downstream sensing surface positioned adjacent the outlet surface of the air filter. Sensing circuitry are connected to the thermoelectric sensors, configured to receive signals from the thermoelectric sensors and process the signals to obtain status information of the air filter.

The present invention relates to an information storage medium and a method for long-term storage of information comprising the steps of: providing a ceramic substrate; coating the ceramic substrate with a layer of a second material different from the material of the ceramic substrate, the layer having a thickness no greater than 10 μm; tempering the coated ceramic substrate to form a writable plate or disc; encoding information on the writable plate or disc by using a laser and/or a focused particle beam to manipulate localized areas of the writable plate or disc.

The present invention relates to an information storage medium and a method for long-term storage of information comprising the steps of: providing a ceramic substrate; coating the ceramic substrate with a layer of a second material different from the material of the ceramic substrate, the layer having a thickness no greater than 10 μm; tempering the coated ceramic substrate to form a writable plate or disc; encoding information on the writable plate or disc by using a laser and/or a focused particle beam to manipulate localized areas of the writable plate or disc.

The present invention relates to an information storage medium and a method for long-term storage of information comprising the steps of: providing a ceramic substrate; coating the ceramic substrate with a layer of a second material different from the material of the ceramic substrate, the layer having a thickness no greater than 10 m; tempering the coated ceramic substrate to form a writable plate or disc; encoding information on the writable plate or disc by using a laser and/or a focused particle beam to manipulate localized areas of the writable plate or disc.

Apparatus and method for aligning a rotatable substrate to a support mechanism to write a feature to the substrate, and a substrate so configured. In some embodiments, the substrate has a circumferentially extending timing pattern with spaced apart first and second timing marks disposed on opposing sides of a center point of the timing pattern and an identification (ID) field that stores a unique identifier value associated with the substrate. Upon mounting of the substrate to a support mechanism that rotates the substrate about a central axis that is offset from the center point, a control circuit generates a compensation value to compensate for the offset using the first and second timing marks and outputs a process instruction to authorize processing of the substrate using the unique identifier value. In some cases, the unique identifier value is used as a lookup to a computerized database.

Apparatus and method for aligning a rotatable substrate to a support mechanism to write a feature to the substrate, and a substrate so configured. In some embodiments, the substrate has a circumferentially extending timing pattern with spaced apart first and second timing marks disposed on opposing sides of a center point of the timing pattern and an identification (ID) field that stores a unique identifier value associated with the substrate. Upon mounting of the substrate to a support mechanism that rotates the substrate about a central axis that is offset from the center point, a control circuit generates a compensation value to compensate for the offset using the first and second timing marks and outputs a process instruction to authorize processing of the substrate using the unique identifier value. In some cases, the unique identifier value is used as a lookup to a computerized database.

Apparatus and method for aligning a rotatable substrate to a support mechanism such as a turntable. The substrate has a circumferentially extending timing pattern comprising at least spaced apart first and second timing marks disposed on opposing sides of a center point of the substrate. The substrate is configured to be mounted to and rotated by the support mechanism about a central axis. The center point of the substrate may be offset from the central axis by an offset distance due to mechanical tolerances associated with the substrate mounting operation. The offset distance may be determined through successive detection of the first and second timing marks by a detector over at least one rotation of the support mechanism and the substrate. A write beam may be adjusted using the determined offset distance to write a second feature to the substrate in alignment with a previously written first feature.