Abstract: Two piezoelectric sensors are mounted on the back of a spring-plate of a mechanical resonance scanner on respective sides of a center line coinciding with an axis of rotation. As the scanner mirror rotates back and forth the two sensors are accelerated and decelerated at a 180.degree. phase difference. Each sensor's output voltage crosses a zero level when the acceleration is unchanging. A differential amplifier detects the zero crossings for motion along the axis of rotation. Common mode rejection eliminates the non-rotational accelerations associated with external vibrations and shocks, and prevents masking the mirror's zero-crossings.

Abstract: Two piezoelectric sensors are mounted on the back of a spring-plate of a mechanical resonance scanner on respective sides of a center line coinciding with an axis of rotation. As the scanner mirror rotates back and forth the two sensors are accelerated and decelerated at a 180.degree. phase difference. Each sensor's output voltage crosses a zero level when the acceleration is unchanging. A differential amplifier detects the zero crossings for motion along the axis of rotation. Common mode rejection eliminates the non-rotational accelerations associated with external vibrations and shocks, and prevents masking the mirror's zero-crossings.

Abstract: A first piezoelectric actuator is located on a first support of a mirror. The first support is elongated having a first portion to one edge of the mirror and a second portion to an opposite edge of the mirror. The actuator drives mirror movement about a first axis of rotation which is orthogonal to a longitudinal axis of the first support. A second piezoelectric actuator is located on a second support of the mirror. The second support is elongated having a first portion to one edge of the mirror and a second portion to an opposite edge of the mirror. The second support is orthogonal to the first support. The second actuator drives mirror movement about a second axis of rotation which is orthogonal to the first axis of rotation and to a longitudinal axis of the second support.

Abstract: A scanning display device directly scans a light source along at least one scanning path, rather than scanning a light beam emitted from such source along such scanning path. By scanning the light source a smaller, lighter weight scanner without a mirror can be used to achieve light source scanning along the desired scan path. A resonant cantilever translates one or more point sources (e.g., one for a monochromatic display; red, green and blue for an RGB display). The cantilever motion is driven by an electromagnetic drive circuit or by a piezoelectric drive actuator. The light source is one or more light emitting diode point sources, one or more a fiber optic point sources, or one or more light emitting polymer light sources.

Abstract: The scanner includes a first spring plate and a second spring plate of common size and shape symmetrically aligned and spaced. A first reflective surface is located at an end of first spring plate. A counter balance mass is located at a corresponding end of the second spring plate. The first spring plate and counter balance mass have common mass and volume and are symmetrically aligned about an axis of symmetry. During a drive cycle, the first spring plate and second spring plate are deflected equally in opposite directions. The first reflective surface and counter balance mass move equally in opposite directions causing the respective movement of the first reflective surface to be counter balanced by the movement of the counter balance mass. The motion is driven by electromagnetic circuits or piezoelectric circuits.

Abstract: A piezoelectric circuit drives mirror movement along a scan path. The scanner includes a support, a reflective surface and a piezoelectric circuit. The support alternately rotates about an axis of rotation in a first direction and a second direction. The reflective surface moves with the support. The piezoelectric circuit is mechanically coupled to the support, and includes a first piezoelectric volume and a second piezoelectric volume. During a first portion of a drive cycle drive signals of opposite polarity cause the volumes to deform in opposing manner. The deformation causes the support to rotate in the first direction. During a second portion of the drive cycle the polarity of the drive signals switches again causing the volumes to deform, but in opposite manner than during the first portion of the drive cycle. The deformation causes the support to rotate in the second direction.

Abstract: Light emitted from a virtual retinal display light source passes through a beamsplitter to a scanning subsystem and on to an eyepiece and the viewer's eye. Some of the light is reflected from the viewer's eye passing back along the same path. Such light however is deflected at the beamsplitter toward a photodetector. The reflected light is detected and correlated to the display scanner's position. The content of the reflected light and the scanner position for such sample is used to generate a map of the viewer's retina. Such map includes `landmarks` such as the viewer's optic nerve, fovea, and blood vessels. The map of the viewer's retina is stored and used for purposes of viewer identification.

Abstract: A display device is achieved using a simplified optical system which generates an expanded exit pupil without compromising magnification or resolution. Modulated light from a source is converged toward a focal point by an optics subsystem. A scanning subsystem deflects the converging light, and thus the focal point, along a raster pattern to define an intermediate image plane. A lens array defines a surface which coincides with the image plane. The lens array includes a plurality of lenses and a polymer dispersed liquid crystal film. The film serves to spread incident light and thus form an expanded exit pupil.

Abstract: An augmented display includes an image display source and a silhouette display source. The image display source generates a virtual image to be perceived by a viewer. The silhouette display source occurs in the path of the background light. The silhouette display source generates a mask corresponding to the image content of the image display. The mask is a darkened area reducing or blocking background light. As the light from the virtual image is overlaid onto the background, there is less background light in the portion where the image appears.

Abstract: An augmented retinal scanning display device includes a multi-functional eyepiece. One function is to direct an image beam onto a viewer's eye. Another function is to correct the vision of the viewer's eye. The display is worn by a viewing person. The eyepiece includes a reflective surface and a transmissive surface. An image beam reflects off the reflective surface onto the viewer's retina enabling the viewer to perceive a virtual image. Background light, such as from the ambient environment or another display device, enters the eyepiece at the transmissive surface and passes through the eyepiece toward the viewer's eye. While passing through the eyepiece, the background light is refracted to correct the viewer's vision.

Abstract: A miniature optical scanner includes an electromagnetic drive having stationary magnets and stationary drive coils to minimize the rotational inertia of the scanner and increase the scanner's resonant frequency. The scanner is such that the resonant frequency is manually tunable as well as automatically adjustable to compensate for variables causing frequency drift. The optical scan angle is increased by employing a multiplying mirror with the optical scanner. For a two axis scanning system, the multiplying mirror may be formed of a second optical scanner to increase the optical scan angle relative to both of the axes.

Abstract: A display device is achieved using a simplified optical system which generates an expanded exit pupil without compromising magnification or resolution. Modulated light from a source is converged toward a focal point by an optics subsystem. A scanning subsystem deflects the converging light, and thus the focal point, along a raster pattern to define a curved intermediate image plane. An exit pupil expanding apparatus defines a curved surface which coincides with the curved image plane. Impinging light rays at a given instant in time span a given incidence angle. Exiting light rays span a larger angle. As a result, the exiting light spans a larger surface area of an ensuing eyepiece. In turn an expanded exit pupil occurs beyond the eyepiece. Embodiments of the expanding apparatus include a curved diffractive optical element, fiber optic face plate, lens array and diffuser. The diffractive optical element generates multiple exit pupils, while the other embodiments generate enlarged exit pupils.

Abstract: Two piezoelectric sensors are mounted on the back of a spring-plate of a mechanical resonance scanner on respective sides of a center line coinciding with an axis of rotation. As the scanner mirror rotates back and forth the two sensors are accelerated and decelerated at a 180.degree. phase difference. Each sensor's output voltage crosses a zero level when the acceleration is unchanging. A differential amplifier detects the zero crossings for motion along the axis of rotation. Common mode rejection eliminates the non-rotational accelerations associated with external vibrations and shocks, and prevents masking the mirror's zero-crossings.

Abstract: A virtual retinal display utilizes photon generation and manipulation to create a panoramic, high resolution, color virtual image that is projected directly onto the retina of the eye. The virtual retinal display includes a source of photons, the photons being modulated with video information and scanned by a scanning system in a raster type of pattern directly onto the retina of the user's eye. A single, monofilament optical fiber of very small diameter couples light from the photon generator to the scanning system so as to provide to the scanning system a point source of light at the fiber's exit aperture. The photon generator may utilize coherent or non-coherent light. Further, the photon generator may utilize color light emitters so as to scan a colored virtual image directly onto the retina of the user's eye.

Abstract: A miniature optical scanner includes an electromagnetic drive having stationary magnets and stationary drive coils to minimize the rotational inertia of the scanner and increase the scanner's resonant frequency. The scanner is such that the resonant frequency is manually tunable as well as automatically adjustable to compensate for variables causing frequency drift. The optical scan angle is increased by employing a multiplying mirror with the optical scanner. For a two axis scanning system, the multiplying mirror may be formed of a second optical scanner to increase the optical scan angle relative to both of the axes.

Abstract: A method for sensing pressure within a work object including placing an electrically deformable member on the work object so as to cover a portion of the surface area thereof; applying electrical energy to the member to cause the member to deform thereby applying pressure to the portion of the surface area of the work object; and sensing the tension in the member as a result of the amount of resistance to deformation imparted by the pressure within the work object.

Abstract: A method for sensing pressure within a work object including placing an electrically deformable member on the work object so as to cover a portion of the surface area thereof; applying electrical energy to the member to cause the member to deform thereby applying pressure to the portion of the surface of the work object; and sensing the tension in the member as a result of the amount of resistance to deformation imparted by the pressure within the work object.