Abstract: The present invention is to provide an optical surface defect inspection apparatus or an optical surface defect inspection method that can improve a signal-to-noise ratio according to a multi-segmented cell method without performing autofocus operations, and can implement highly sensitive inspection. The present invention is an optical surface defect inspection apparatus or an optical surface defect inspection method in which an inspection beam is applied onto a test subject, an image of a scattered light from the surface of the test subject is formed on a photo-detector, and a defect on the surface of the test subject is inspected based on an output from the photo-detector. The photo-detector has an optical fiber bundle. One end thereof forms a circular light receiving surface to receive the scattered light. The other end thereof is connected to a plurality of light receiving devices.

Abstract: The present invention provides an apparatus and method which enable detecting a microscopic defect sensitively by efficiently collecting and detecting scattering light from a defect in a wider region without enlarging the apparatus. In the apparatus for inspecting a defect on a surface of a sample, including illumination means which irradiates a surface of a sample with laser, reflected light detection means which detects reflected light from the sample, and signal processing means which processes a detected signal and detecting a defect on the sample, the reflected light detection means is configured to include a scattering light detection unit which collects scattering light components of the reflected light from the sample by excluding specularly reflected light components by using an aspheric flannel lens and detecting the scattering light components.

Abstract: The present invention provides an apparatus and method which enable detecting a microscopic defect sensitively by efficiently collecting and detecting scattering light from a defect in a wider region without enlarging the apparatus. In the apparatus for inspecting a defect on a surface of a sample, including illumination means which irradiates a surface of a sample with laser, reflected light detection means which detects reflected light from the sample, and signal processing means which processes a detected signal and detecting a defect on the sample, the reflected light detection means is configured to include a scattering light detection unit which collects scattering light components of the reflected light from the sample by excluding specularly reflected light components by using an aspheric flannel lens and detecting the scattering light components.

Abstract: The present invention relates to a disk protrusion detection/flatness measurement circuit and a disk glide tester, in which protrusion detection and average value calculation can be performed without switching signal processing circuits of two systems, one for the protrusion detection of a disk and the other for the average value calculation with respect to a track or a sector of the disk. This also makes it possible to reduce the size of the measurement circuit. In the protrusion detection/flatness measurement circuit, a signal from a protrusion detection sensor is amplified and converted from an analog signal to a digital signal. The signal passes through a band-pass filter to obtain a digital signal with a predetermined bandwidth. Then, peak detection and average value calculation processes are applied in parallel to the obtained digital signal. Thus, pass/fail decision of the disk can be made based on the detected peak and average values.

Abstract: The present invention provides an apparatus and method which enable detecting a microscopic defect sensitively by efficiently collecting and detecting scattering light from a defect in a wider region without enlarging the apparatus. In the apparatus for inspecting a defect on a surface of a sample, including illumination means which irradiates a surface of a sample with laser, reflected light detection means which detects reflected light from the sample, and signal processing means which processes a detected signal and detecting a defect on the sample, the reflected light detection means is configured to include a scattering light detection unit which collects scattering light components of the reflected light from the sample by excluding specularly reflected light components by using an aspheric flannel lens and detecting the scattering light components.

Abstract: The present invention provides an apparatus and method which enable detecting a microscopic defect sensitively by efficiently collecting and detecting scattering light from a defect in a wider region without enlarging the apparatus. In the apparatus for inspecting a defect on a surface of a sample, including illumination means which irradiates a surface of a sample with laser, reflected light detection means which detects reflected light from the sample, and signal processing means which processes a detected signal and detecting a defect on the sample, the reflected light detection means is configured to include a scattering light detection unit which collects scattering light components of the reflected light from the sample by excluding specularly reflected light components by using an aspheric flannel lens and detecting the scattering light components.

Abstract: In order to implement efficient read/write testing by firstly determining read/write test area-sampling positions based on position information relating to any defects detected during optical inspection, and then conducting read/write tests only upon areas neighboring the defects detected during the optical inspection, a magnetic disk to be inspected is retained on a spindle and moved under this state between an optical type of inspection apparatus and a read/write test apparatus, in which apparatus configuration the read/write test apparatus uses position information on any defects detected by the optical type of inspection apparatus and conducts read/write tests only upon neighboring areas of the defects detected by the optical type of inspection apparatus.

Abstract: The present invention provides an apparatus and method which enable detecting a microscopic defect sensitively by efficiently collecting and detecting scattering light from a defect in a wider region without enlarging the apparatus. In the apparatus for inspecting a defect on a surface of a sample, including illumination means which irradiates a surface of a sample with laser, reflected light detection means which detects reflected light from the sample, and signal processing means which processes a detected signal and detecting a defect on the sample, the reflected light detection means is configured to include a scattering light detection unit which collects scattering light components of the reflected light from the sample by excluding specularly reflected light components by using an aspheric flannel lens and detecting the scattering light components.

Abstract: The present invention is to provide an optical surface defect inspection apparatus or an optical surface defect inspection method that can improve a signal-to-noise ratio according to a multi-segmented cell method without performing autofocus operations, and can implement highly sensitive inspection. The present invention is an optical surface defect inspection apparatus or an optical surface defect inspection method in which an inspection beam is applied onto a test subject, an image of a scattered light from the surface of the test subject is formed on a photo-detector, and a defect on the surface of the test subject is inspected based on an output from the photo-detector. The photo-detector has an optical fiber bundle. One end thereof forms a circular light receiving surface to receive the scattered light. The other end thereof is connected to a plurality of light receiving devices.

Abstract: In order to enable a highly-sensitive certifying test by detecting a signal with a high S/N ratio while controlling the glide height of a magnetic head to be optimized at the time of the certifying test, a method for inspecting a magnetic disk by conducting the certifying test for the magnetic disk using the magnetic head incorporating a heater includes: writing data into the magnetic disk using the magnetic head; and reading the data written into the magnetic disk using the magnetic head. Electric power applied to the heater incorporated in the magnetic head is switched between when writing the data and when reading the data.

Abstract: An object of the present invention is to provide a deterioration detection method of a head and a magnetic disk inspection apparatus in which the number of times of exchanging the head due to deterioration is decreased to improve the throughput of an inspection. In the present invention, a resistance value detecting circuit that is directly coupled to both terminals of an MR head is provided to measure the resistance value of the MR head, and the measured value is compared with the initial value of the exchanged head, so that it is possible to recognize a deterioration state of each head irrespective of a magnetic disk as a measurement target.

Abstract: The present invention provides a method for measuring an optimum seeking time and an inspection apparatus using this method capable of measuring and setting an optimum seeking time for inspection of a magnetic disk or magnetic head. The method samples average level differences of sector-wise read signals in positive and negative domains for one round of track and detects a minimum value H and a minimum value L among these differences. The method recalculates the seeking time while changing the settling time. After writing and reading test data, calculates a deviation DEV of average levels DEV=(H?L)/(H+L). The method is adapted to obtain a minimum one of the values of settling time having measured when the deviation DEV of average levels is equal to or less than a predetermined value as an optimum settling time or an optimum seeking time.

Abstract: In order to implement efficient read/write testing by firstly determining read/write test area-sampling positions based on position information relating to any defects detected during optical inspection, and then conducting read/write tests only upon areas neighboring the defects detected during the optical inspection, a magnetic disk to be inspected is retained on a spindle and moved under this state between an optical type of inspection apparatus and a read/write test apparatus, in which apparatus configuration the read/write test apparatus uses position information on any defects detected by the optical type of inspection apparatus and conducts read/write tests only upon neighboring areas of the defects detected by the optical type of inspection apparatus.

Abstract: A test burst signal is overwritten from a write end position over a connecting region determined by positional deviation between a read head and a write head and a peripheral speed of a disk. Since, therefore, the overwritten signal portion is overlapped on the test burst signal written at a write start point, it is possible to reduce a width of the connecting region to thereby reduce a test inhibit region.

Abstract: The present invention provides an apparatus and method which enable detecting a microscopic defect sensitively by efficiently collecting and detecting scattering light from a defect in a wider region without enlarging the apparatus. In the apparatus for inspecting a defect on a surface of a sample, including illumination means which irradiates a surface of a sample with laser, reflected light detection means which detects reflected light from the sample, and signal processing means which processes a detected signal and detecting a defect on the sample, the reflected light detection means is configured to include a scattering light detection unit which collects scattering light components of the reflected light from the sample by excluding specularly reflected light components by using an aspheric flannel lens and detecting the scattering light components.

Abstract: The present invention relates to a disk protrusion detection/flatness measurement circuit and a disk glide tester, in which protrusion detection and average value calculation can be performed without switching signal processing circuits of two systems, one for the protrusion detection of a disk and the other for the average value calculation with respect to a track or a sector of the disk. This also makes it possible to reduce the size of the measurement circuit. In the protrusion detection/flatness measurement circuit, a signal from a protrusion detection sensor is amplified and converted from an analog signal to a digital signal. The signal passes through a band-pass filter to obtain a digital signal with a predetermined bandwidth. Then, peak detection and average value calculation processes are applied in parallel to the obtained digital signal. Thus, pass/fail decision of the disk can be made based on the detected peak and average values.

Abstract: An object of the present invention is to provide a deterioration detection method of a head and a magnetic disk inspection apparatus in which the number of times of exchanging the head due to deterioration is decreased to improve the throughput of an inspection. In the present invention, a resistance value detecting circuit that is directly coupled to both terminals of an MR head is provided to measure the resistance value of the MR head, and the measured value is compared with the initial value of the exchanged head, so that it is possible to recognize a deterioration state of each head irrespective of a magnetic disk as a measurement target.

Abstract: The present invention provides a method for measuring an optimum seeking time and an inspection apparatus using this method capable of measuring and setting an optimum seeking time for inspection of a magnetic disk or magnetic head. The method samples average level differences of sector-wise read signals in positive and negative domains for one round of track and detects a minimum value H and a minimum value L among these differences. The method recalculates the seeking time while changing the settling time. After writing and reading test data, calculates a deviation DEV of average levels DEV=(H?L)/(H+L). The method is adapted to obtain a minimum one of the values of settling time having measured when the deviation DEV of average levels is equal to or less than a predetermined value as an optimum settling time or an optimum seeking time.

Abstract: A test burst signal is overwritten from a write end position over a connecting region determined by positional deviation between a read head and a write head and a peripheral speed of a disk. Since, therefore, the overwritten signal portion is overlapped on the test burst signal written at a write start point, it is possible to reduce a width of the connecting region to thereby reduce a test inhibit region.

Abstract: Acceptability of a disk is determined by passing a detection signal from a head through a low-pass filter to obtain a detection signal component corresponding to side runout of the disk due to rotation of the disk and by comparing the maximum level of the signal with a predetermined reference value. Thus, it is possible to extract unacceptable disk which causes erroneous write and/or read or clash due to surface undulation of disk, even when the disk has no protrusion having bad influence upon the disk.