Optical head and data processing apparatus including the same

An optical data processing apparatus, which is selectively loadable with a first and second types of the data storage media in order to read and/or write data from/on a loaded data storage medium, the first type of the data storage medium being single-layered, the second type of the data storage medium being multi-layered, the optical data processing apparatus comprising:

• a light source for radiating light;
• a focusing optical system for forming a focal spot by condensing the light that has been emitted from the light source;
• a light detector, which includes at least one photodetector for receiving the light and generating a light quantity signal representing quantity of the light received;
• a detecting optical system for guiding a light beam, which has been reflected from a data storage layer, to the light detector;
• and
• a signal processor for generating a medium sensing signal from the light quantity signal and recognizing the type of the loaded data storage medium by the medium sensing signal,
• wherein the light detector includes, as the at least one photodetector, a layer sensing photodetector arranged in view of an area of the light detector where a reflected light beam from a storage layer other than the storage layer, near which the focal spot is located, is incident when the second type of the data storage media is loaded and
• wherein the light detector further includes a photodetector which receives the reflected light beam to generate a focus error signal and which is different from the layer sensing photodetector.

An optical head for reading and/or writing data from/on a data storage medium, in which storage layers are stacked, the optical head comprising:

• a light source for radiating light;
• a focusing optical system for forming a focal spot by condensing the light that has been emitted from the light source;
• a light detector, which includes at least one photodetector for receiving the light and generating a light quantity signal representing quantity of the light received;
• a detecting optical system for guiding reflected light beams, which have been reflected from the storage layers, respectively, to the light detector;
• and
• a signal processor for generating a layer sensing signal from the light quantity signal and, by the layer sensing signal, determining which of the storage layers of the loaded data storage medium the focal spot is located near,
• wherein the light detector includes, as the at least one photodetector, a layer sensing photodetector arranged in view of an area of the light detector where a reflected light beam from a storage layer other than the determined storage layer, near which the focal spot is located, is incident, and
• wherein the light detector further includes a photodetector which receives the reflected light beam to generate a focus error signal and which is different from the layer sensing photodetector.

An optical head for reading and/or writing data from/on first and second types of the data storage media selectively, the first type of the data storage medium being single-layered, the second type of the data storage medium being multi-layered, the optical head comprising:

• a light source for radiating light;
• a focusing optical system for forming a focal spot by condensing the light that has been emitted from the light source;
• a light detector, which includes at least one photodetector for receiving the light and generating a light quantity signal representing quantity of the light received;
• a detecting optical system for guiding a light beam, which has been reflected from a data storage layer, to the light detector;
• and
• a signal processor for generating a medium sensing signal from the light quantity signal and recognizing the type of the loaded data storage medium by the medium sensing signal,
• wherein the light detector includes, as the at least one photodetector, a layer sensing photodetector arranged in view of first and second areas of the light detector, where, in the first area, a reflected light beam from the storage layer, near which the focal spot is located, is incident when the first type of the data storage media is loaded, and where in the second area, a reflected light beam from a storage layer other than the storage layer, near which the focal spot is located, is incident when the second type of the data storage media is loaded and
• wherein the light detector further includes a photodetector which receives the reflected light beam to generate a focus error signal and which is different from the layer sensing photodetector.

A signal processor to be built in an optical data processing apparatus for reading and/or writing data from/on a data storage medium, in which storage layers are stacked, the apparatus comprising:

• a light source for radiating light;
• a focusing optical system for forming a focal spot by condensing the light that has been emitted from the light source;
• a light detector, which includes at least one photodetector for receiving the light and generating a light quantity signal representing quantity of the light received;
• and
• a detecting optical system for guiding reflected light beams, which have been reflected from the storage layers, respectively, to the light detector,
• wherein the light detector includes, as the at least one photodetector, a layer sensing photodetector arranged in view of an area of the light detector where a reflected light beam from a storage layer other than the determined storage layer, near which the focal spot is located, is incident, and
• wherein the light detector further includes a photodetector which receives the reflected light beam to generate a focus error signal and which is different from the layer sensing photodetector,
• wherein the signal processor generates a layer sensing signal from the light quantity signal and, by the layer sensing signal, determines which of the storage layers of the loaded data storage medium the focal spot is located near.

A signal processor to be built in an optical data processing apparatus, which is selectively loadable with a first and second types of the data storage media in order to read and/or write data from/on a loaded data storage medium, the first type of the data storage medium being single-layered, the second type of the data storage medium being multi-layered, the apparatus comprising:

• a light source for radiating light;
• a focusing optical system for forming a focal spot by condensing the light that has been emitted from the light source;
• a light detector, which includes at least one photodetector for receiving the light and generating a light quantity signal representing quantity of the light received;
• and
• a detecting optical system for guiding a light beam, which has been reflected from a data storage layer, to the light detector;
• wherein the light detector includes, as the at least one photodetector, a layer sensing photodetector arranged in view of an area of the light detector where a reflected light beam from a storage layer other than the storage layer, near which the focal spot is located, is incident when the second type of the data storage media is loaded and
• wherein the light detector further includes a photodetector which receives the reflected light beam to generate a focus error signal and which is different from the a layer sensing photodetector, and
• wherein the signal processor for generating a medium sensing signal from the light quantity signal and recognizing the type of the loaded data storage medium by the medium sensing signal.

An optical data processing apparatus for reading and/or writing data from/on a data storage medium, in which storage layers are stacked, the apparatus comprising:

• a light source for radiating light;
• a focusing optical system for forming a focal spot by condensing the light that has been emitted from the light source;
• a light detector, which includes at least one photodetector for receiving the light and generating a light quantity signal representing quantity of the light received;
• a detecting optical system for guiding reflected light beams, which have been reflected from the storage layers, respectively, to the light detector;
• and
• a signal processor for generating a layer sensing signal from the light quantity signal and, by the layer sensing signal, determining which of the storage layers of the loaded data storage medium the focal spot is located near,
• wherein the light detector includes, as the at least one photodetector, a layer sensing photodetector arranged in view of an area of the light detector where a reflected light beam from a storage layer other than the determined storage layer, near which the focal spot is located, is incident, and
• wherein the light detector further includes a photodetector which receives the reflected light beam to generate a data signal representing data and which is different from the layer sensing photodetector.

An optical data processing apparatus, which is selectively loadable with a first and second types of the data storage media in order to read and/or write data from/on a loaded data storage medium, the first type of the data storage medium being single-layered, the second type of the data storage medium being multi-layered, the optical data processing apparatus comprising:

• a light source for radiating light;
• a focusing optical system for forming a focal spot by condensing the light that has been emitted from the light source;
• a light detector, which includes at least one photodetector for receiving the light and generating a light quantity signal representing quantity of the light received;
• a detecting optical system for guiding a light beam, which has been reflected from a data storage layer, to the light detector;
• and
• a signal processor for generating a medium sensing signal from the light quantity signal and recognizing the type of the loaded data storage medium by the medium sensing signal,
• wherein the light detector includes, as the at least one photodetector, a layer sensing photodetector arranged in view of an area of the light detector where a reflected light beam from a storage layer other than the storage layer, near which the focal spot is located, is incident when the second type of the data storage media is loaded and
• wherein the light detector further includes a photodetector which receives the reflected light beam to generate a data signal representing data and which is different from the layer sensing photodetector.

An optical data processing apparatus for reading and/or writing data from/on a data storage medium, in which storage layers are stacked, the apparatus comprising:

• a light source for radiating light;
• a focusing optical system for forming a focal spot by condensing the light that has been emitted from the light source;
• a light detector, which includes at least one photodetector for receiving the light and generating a light quantity signal representing quantity of the light received;
• a detecting optical system for guiding reflected light beams, which have been reflected from the storage layers, respectively, to the light detector;
• and
• a signal processor for generating a layer sensing signal from the light quantity signal and, by the layer sensing signal, determining which of the storage layers of the loaded data storage medium the focal spot is located near,
• wherein the light detector includes, as the at least one photodetector, a layer sensing photodetector arranged in view of an area of the light detector where a reflected light beam from a storage layer other than the determined storage layer, near which the focal spot is located, is incident, and
• wherein the layer sensing photodetector receives a part of the reflected light beam in which no optical axis is included.

An optical data processing apparatus, which is selectively loadable with a first and second types of the data storage media in order to read and/or write data from/on a loaded data storage medium, the first type of the data storage medium being single-layered, the second type of the data storage medium being multi-layered, the optical data processing apparatus comprising:

• a light source for radiating light;
• a focusing optical system for forming a focal spot by condensing the light that has been emitted from the light source;
• a light detector, which includes at least one photodetector for receiving the light and generating a light quantity signal representing quantity of the light received;
• a detecting optical system for guiding a light beam, which has been reflected from a data storage layer, to the light detector;
• and
• a signal processor for generating a medium sensing signal from the light quantity signal and recognizing the type of the loaded data storage medium by the medium sensing signal,
• wherein the light detector includes, as the at least one photodetector, a layer sensing photodetector arranged in view of an area of the light detector where a reflected light beam from a storage layer other than the storage layer, near which the focal spot is located, is incident when the second type of the data storage media is loaded and
• wherein the layer sensing photodetector receives a part of the reflected light beam in which no optical axis is included.