The imaging properties of optical microscopes are often compromised by aberrations that reduce image resolution and contrast. Adaptive optics technology has been employed in various systems to correct these aberrations and restore performance. This has required various departures from the traditional adaptive optics schemes that are used in astronomy. This review discusses the sources of aberrations, their effects and their correction with adaptive optics, particularly in confocal and two-photon microscopes. Different methods of wavefront sensing, indirect aberration measurement and aberration correction devices are discussed. Applications of adaptive optics in the related areas of optical data storage, optical tweezers and micro/nanofabrication are also reviewed.

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Adaptive optics in microscopy

A stereoscopic image display device includes a substrate; a plurality of black matrices formed parallel to one another on a first surface of the substrate; a plurality of black stripes formed on a second surface of the substrate opposite the first surface, each of the plurality of black stripes corresponding to one of the plurality of black matrices, each of the plurality of black stripes having a width equal to or greater than a width of the corresponding one of the plurality of black matrices; and a patterned retarder film formed on the plurality of black stripes, the patterned retarder film including a plurality of first retarder patterns and a plurality of second retarder patterns, wherein a first retarder pattern is disposed over a region between a first pair of black stripes, and a second retarder pattern is disposed over a region between a second pair of black stripes that is adjacent to the first pair of black stripes, and wherein the width of each of the plurality of black stripes is less than or equal to twice an adhesion margin of the patterned retarder film.

Stereoscopic image display device

To provide methods and system for creating focal planes in virtual and augmented reality.SOLUTION: Configurations are disclosed for presenting virtual reality and augmented reality experiences to users. The system may comprise a spatial light modulator operatively coupled to an image source to project light associated with one or more frames of image data, and a variable focus element (VFE) for varying a focus of the projected light such that a first frame of the image data is focused at a first depth plane, and a second frame of the image data is focused at a second depth plane, where a distance between the first depth plane and the second depth plane is fixed.SELECTED DRAWING: Figure 5

Methods and system for creating focal planes in virtual and augmented reality

An imaging arrangement and method for extended the depth of focus are provided. The imaging arrangement comprises an imaging lens having a certain affective aperture, and an optical element associated with said imaging lens. The optical element is configured as a phase-affecting, non-diffractive optical element defining a spatially low frequency phase transition. The optical element and the imaging lens define a predetermined pattern formed by spaced-apart substantially optically transparent features of different optical properties. Position of at least one phase transition region of the optical element within the imaging lens plane is determined by at least a dimension of said affective aperture.

Optical method and system for extended depth of focus

An optical lens system for taking image comprises, in order from the object side to the image side: a first lens element with positive refractive power having a convex object-side surface; an aperture stop; a second lens element with negative refractive power; a third lens element having a convex object-side surface; and a fourth lens element with negative refractive power having a concave object-side surface, an image-side surface of the fourth lens element being aspheric and formed with inflection points. A distance from the image-side surface of the fourth lens element to an image plane along an optical axis being BFL, a total track length of the optical lens system for taking image being TTL, and they satisfy the relation: BFL/TTL>0.12. In the optical lens system for taking image, the number of lens elements with refractive power being limited to four.

Optical lens system for taking image

An optical pickup for use in a multi-layer disc playback apparatus for playing back a multi-layer disc having a plurality of recording layers including a wave front aberration correcting means that is disposed in an optical path between a light source and an objective lens and corrects wave front aberration of light emitted from the light source in accordance with a recording layer to be played back.

Optical pickup and multi-layer disc playback apparatus

We have studied the next-generation digital versatile disk (DVD) using a blue laser and investigated the application of a liquid crystal (LC) panel to the high-density disk. The LC panel can easily shift the optical path length of light beams making it possible to cancel out wavefront aberrations. First, the authors applied an LC panel to a tilt servo system. Compared with a mechanical tilt servo system, the LC tilt servo is expected to be more compact and reliable. We also developed a system for sensing the amount of disk tilt by comparing the signal levels of crosstalk from adjacent tracks. Consequently a tilt servo without any extra sensors was achieved. Another application of the LC panel is for the compensation of spherical aberrations. It was confirmed, by simulations and experiments, that the LC panel was practically useful for correcting disk thickness error which has been determined to become more serious when a blue laser was used.

The applications of a liquid crystal panel for the 15 gbyte optical disk systems

To confirm the feasibility of realizing subterabyte or terabyte optical memories, we evaluated a multilayer read-only disk having 20 information layers. We propose a new disk structure, which is an alternative structure to reduce interlayer crosstalk, optimized by computer simulations. We fabricated multilayer read-only optical disks using a conventional manufacturing process for Blu-ray disk (BD) dual-layer media. Moreover, we improved the reproduction system to compensate for the large spherical aberration. From the experimental results, we obtained sufficiently low jitter values reproduced from a 20-layer disk. We confirmed the feasibility of the multilayer read-only disk with a capacity of 500 Gbytes.

Multilayer 500 Gbyte Optical Disk

An aberration correcting apparatus for correcting an aberration of beam which is emitted from a light source and focused on an information recording medium by an optical system, the aberration correcting apparatus includes a wave front aberration correcting component aligned in an optical path between the light source and the information recording medium for correcting a wave front aberration of an incident beam by changing a refractive index corresponding to an applied voltage. A detector also detects a tilt-angle of the information recording medium, and a controller for controlling the wave front aberration correcting component corresponding to an output of the detector.

Aberration correcting apparatus and information recording medium play-back apparatus

An optical pickup includes: a light source, an object lens, and an aberration correction unit for correcting aberration by giving a phase difference to a light beam. The aberration correction unit corrects astigmatism caused by an optical system of the optical pickup.

Masakazu Ogasawara

Papers

Optical pickup and multi-layer disc playback apparatus

The applications of a liquid crystal panel for the 15 gbyte optical disk systems

Multilayer 500 Gbyte Optical Disk

Aberration correcting apparatus and information recording medium play-back apparatus

Optical pickup, aberration correction unit and astigmatism measurement method