Hewlett-packard Company

Hewlett-packard Development Company, L.P.

Other

Daniel R. Marshall

David K. Campbell

David K. Towner

Bernard W., Jr. Bell

Daniel R Marshall

David K Towner

David Kay Campbell

Robert J Lawton

Bernard W Bell, Jr

Jr Bell Bernard W

This focus sensor is readily usable in a system using pupil obscuration to measure the state of focus of a light beam. A scattering volumetric filter modifies a three-dimensional wavefront so that focus can be detected by a two-dimensional detector for conversion to a one-dimensional signal having values of plus, zero and minus. This diffusing filter comprises sub wavelength particles having a high index of refraction suspended in an adhesive to produce a solid diffuser. This focus sensor enables a well-behaved focus curve having a constant slope near best focus, while maintaining a slope that is either constant or monotonic at a minimal rate over an extended distance to support a long capture-range over which a focus-controlling servo-mechanism can acquire and maintain focus in the presence of corrupting target surface topography or optical defects.

Three-dimensional filter enables adaptive focus sensing

An autofocus system adaptable for use in microscopes or other optical systems incorporates an auxiliary photodetector that measures light only from a reference light source. An outgoing reference beam, incident upon a target to be inspected, is reflected to become an incoming reference beam incident on a photodetector. The photodetector generates a focus error signal proportional to the displacement of the target from the ideal focal point. The auxiliary photodetector generates a correction signal proportional to the output of the reference light source. The correction signal is used to compensate the focus error signal for stray light generated by the reference light source. The compensated focus error signal may be used to drive a servomechanism to displace either the target or the microscope objective lens to bring the target into focus. The correction signal may also be used to compensate the reference light source gain to control the reference light source output.

Autofocus system with stray light compensation

A focus sensing system adaptable for use in microscopes or other optical systems incorporates a selective beam block. An outgoing reference beam, incident upon a target to be inspected, is reflected to become an incoming reference beam. A beam block inserted within the optical system selectively rejects unwanted reflections from surfaces other than the target allowing the desired incoming reference beam to be photodetected without interference from reflections off of surfaces that are not of interest. The photodetector generates an electronic signal corresponding to the displacement of the target from the ideal focal point. The electrical signal may be used to drive a servomechanism to displace either the target or the microscope objective lens to bring the target into focus.

Removal of unwanted reflections in autofocus systems

A distance measuring device capable of being used in microscopes or other optical systems. Embodiments of the invention employ one or more scanning mirrors to scan a reference beam over a target to be inspected. The reference beam is returned and detected by a photodetector. The reference beam may be created by using a knife-edge element which allows the outgoing reference beam and incoming reference beam to follow the same path so that the apparent motion of the spot on the target surface is not detected by the photodetector. The photodetector generates an electronic signal corresponding to the displacement of the target away from the ideal focal point. The electrical signal may be used to drive a servomechanism to displace either the target or the microscope objective lens to bring the target in focus.

Distance measuring system

An X-ray generating apparatus comprises a semiconductor structure, an emitter formed on the semiconductor structure, with the emitter to emit electrons. The apparatus further comprises an element to generate X-rays in response to impact by the electrons on the element.

X-ray generating apparatus having an emitter formed on a semiconductor structure

A storage device including many field emitters in close proximity to a storage medium, and a micromover, all in a partial vacuum. Each field emitter can generate an electron beam current. The storage medium has many storage areas on it, with each field emitter responsible for a number of storage areas. Also, each storage area can be in a number of different states to represent the information stored in that area. In storing information to the storage device, the power density of an electron beam current is increased to change the state of the storage area bombarded by the electron beam current. In reading information from the device, the power density of the electron beam current is reduced to generate a signal current from the storage area bombarded by the electron beam current. During reading, the power density is selected to be low enough so that no writing occurs. The magnitude of the signal current depends on the state of the storage area. The information stored in the storage area is read by measuring the magnitudes of the signal current. An electron beam steering mechanism deflects the electron beam current to different ones of the storage areas.

Ultra-high density storage device with electron beam steering

A swallowable data recorder medical device includes a capsule including a sensing module for sensing a biologic condition within a body. A recording module is provided including an atomic resolution storage device. The recording module is electrically coupled to the sensing module for recording data representative of the sensed biologic condition in the atomic resolution storage device. A power supply is coupled to the recording module.

Swallowable data recorder capsule medical device

A storage device including many field emitters in close proximity to a storage medium, and a micromover, all in a partial vacuum. Each field emitter can generate an electron beam current. The storage medium has many storage areas on it, with each field emitter responsible for a number of storage areas. Also, each storage area can be in a number of different states to represent the information stored in that area. In storing information to the storage device, the power density of an electron beam current is increased to change the state of the storage area bombarded by the electron beam current. In reading information from the device, the power density of the electron beam current is reduced to generate a signal current from the storage area bombarded by the electron beam current. During reading, the power density is selected to be low enough so that no writing occurs. The magnitude of the signal current depends on the state of the storage area. The information stored in the storage area is read by measuring the magnitudes of the signal current. The micromover scans the storage medium with respect to the field emitters so that each field emitter can access many storage areas. The micromover causes a periodic change in the relative positions between the field emitters and the storage medium, thereby generating periodic field emitter trajectories.

Ultra-high density storage device with resonant scanning micromover

The present invention provides a swallowable data recorder medical device. The swallowable data recorder medical device includes a capsule including a sensing module for sensing a biologic condition within a body. A recording module is provided including an atomic resolution storage device. The recording module is electrically coupled to the sensing module for recording data representative of the sensed biologic condition in the atomic resolution storage device. A power supply is coupled to the recording module.

A double-pass projection display system with separate polarizers and analyzers. One embodiment of the invention includes an input polarizer, a color separation/recombination device, and a number of image producing sections. The input polarizer receives unpolarized white light and polarizes this light. The color separation/recombination device receives the polarized white light and separates this light into a number of component color bands. The color separation/recombination device then supplies a component color band to each image producing sections. Each section includes a spatial light modulator and an output analyzer. The spatial light modulator modulates the color band that the image producing section receives from the color separation/recombination device. The output analyzer then (1) discards the light, in the modulated band, that has a first polarization state, and (2) directs the light, in the modulated band, that has a second polarization state to the color separation/recombination device. The color separation/recombination device then produces a single color light by combining the component color bands that it receives from the output analyzers of the image producing sections.

Double-pass projection displays with separate polarizers and analyzers

A system and method of providing a periodic trajectory scan path for a laser beam across a photoconductive surface in a laser printer. A preferred embodiment of the periodic trajectory for a system with a two-axis deflector includes a multiple-frequency omega wave trajectory for providing a substantially rectangular grid of available dot locations for selective laser beam pulsing. As such, a plurality of generally linear rows of dots are completed in a single scan pass of the laser beam across the surface. The periodic trajectory is provided by deflecting the laser beam with an optical beam deflector, such as an electro-optic deflector, placed between the laser and the rotating polygon scanning mirror. A preferred embodiment of the beam deflector includes a folded optical path.

Beam deflecting for enhanced laser printer scanning

A system and method of deflecting a laser beam in a laser printer for providing enhanced resolution and reduced banding effects. Specifically, to enhance resolution, the laser beam is borrowed (deflected) from a white space area adjacent an image to double resolution at the edges of the image. Similarly, banding is reduced by deflecting the beam to compensate for drum rotational and translational errors. The beam is deflected using an electro-optic modulator placed between the laser diode and the scanning mirror. Encoders detect drum rotational errors and motion between the optics unit and the drum to provide a closed loop feedback system for reducing banding.

Beam deflecting for resolution enhancement and banding reduction in a

A miniature rotary actuator optical head assembly incorporating data and servo detecting elements mounted inside a source/detector module, which is located on the rotary actuator arm adjacent to the pivot point of the rotary actuator arm. The miniature rotary actuator optical head also includes a miniature focus motor which supports a fold mirror and an objective lens and repositions the fold mirror and objective lens simultaneously whenever a focus error is received. The focus motor can be actuated by a magnetic bias field that originates external to the rotary actuator arm, particularly the magnetic bias field generated for magneto-optical recordation. The optical assembly may also include two stage tracking by mounting the light source on a pair of lateral movement flexures and supplying a fine tracking error signal to actuate the movement of the light source.

Subminiature rotary actuator optical head

A method and apparatus for producing position error signals from a beam of light, called an input light beam, reflected from an optical surface of recording media, employs a detector prism which has a steep angle, reflection/transmission interface. A prism, such as a dove prism, separate from the detector prism, or other optical structure, integral with the detector prism, having one or more Brewster angle faces on which the input light beam is incident, is employed for inverting a portion of equal portions of the input light beam prior to incidence of the resulting beam on the reflection/transmission interface of the detector prism. Crossing of the marginal rays in the transmitted and reflected complementary light beams now does not invert the slope of the error signal. Now the error signal is not bilaterally sensitive in the respective complementary light beams. The signal instead is now generated by the difference in the total light energy in the respective transmitted and reflected complementary light beams.

Optical position error detection using complementary steep angle

A method and apparatus for detecting the focus of a beam of light directed onto grooved optical media, wherein light reflected from said media has a number of orders of reflection forming a sheared interferogram, and wherein overlapping regions are generated between said orders of reflection in said interferogram, is shown to include a light receiving member for receiving light reflected from the media and for directing the light onto a detector member for detecting differences in the brightness of light across the overlapping regions. The detecting member is shown to include, a first photosensitive member for detecting the brightness of light in a portion of the overlap region between the zeroth and first order reflections, a second photosensitive member for detecting the brightness of light in the remainder of the overlap region between the zeroth and first order reflections, and a comparator for comparing the brightness detected between the portion and the remainder of the overlap region.

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Boise, ID, United States of America

Daniel R Marshall