Yourii Martynov

43.4: High Brightness Direct LED Backlight for LCD-TV

A novel LED light source, “Luxeon Direct”, has been integrated into a highly efficient direct backlight. This concept incorporates one of the latest LEDs released by Lumileds™. This direct backlight approach integrates side emitting LEDs with a highly reflective cavity placed behind the LCD. Prior to this method it has been very difficult to use high power red, green and blue (RGB) LEDs in a direct backlight design due to the high color and brightness uniformity requirements. In this paper a method will be demonstrated that can achieve excellent backlight performance using an indirect illumination approach with high power LEDs.

43.3: High‐efficiency Slim LED Backlight System with Mixing Light Guide

We have developed a novel optical system for an edge-lit LED backlight. The system uses high-power red, green and blue LEDs and has a minimum thickness despite the arrangement for color mixing. The components of the system have been optimized enabling high optical efficiency while maintaining low cost and good manufacturability. Furthermore, conceptually the system is very close to the existing CCFL backlights and allows re-use of the existing components and infrastructure.

High Numerical Aperture Optical Recording : Active Tilt Correction or Thin Cover Layer?

Playback of a 12 cm diameter replicated ROM disc with a 0.6 mm substrate thickness and a storage capacity of 10 GB has been achieved using a light path with a dual-lens objective with NA=0.85 and active tilt control. The disc tilt margin exceeds ±0.7 degree. Also backward compatibility with digital versatile disc (DVD) has been demonstrated. Active tilt correction is not required for read out of a disc with a 0.1 mm transparent cover layer. This technique has also been studied experimentally. The merits and disadvantages of the two approaches are discussed.

An Integrated Magneto-Optical Sliding Head for First Surface Laser Pulsed Magnetic Field Modulation Magneto-Optical-Recording

A sliding head with integrated focusing lens and magnetic field modulation coil has been designed and manufactured. The component can be used for high data rate, first surface magneto optical recording with a NA=0.85 and λ=400 nm. A coil is integrated into the air bearing surface of a slider to maintain a head-disk distance of around 1 µm. It can generate at least a 200 MHz modulated magnetic field of 15 kA/m fieldstrength. We have tested the coil, slider performance and two stage tracking by using a flat 0.6 mm thick slider.

High-density first surface magneto-optical recording using blue laser high-numerical aperture objective and flying slider

We present a magneto-optical recording head designed for a 400 nm laser with a 0.85 numerical aperture doublet objective lens and a thin film Magnetic Field Modulation coil integrated in a flying slider.

Static Tester for Characterization of Optical Near-Field Coupling Phenomena

We present an experimental set-up for systematical studies of optical near-field coupling phenomena using a solid immersion lens (SIL) to surpass the conventional far field diffraction limit. The set-up incorporates a microscope objective lens with NA equals 0.80 in combination with a hemispherical SIL manufactured from glass with refractive index n equals 1.887 and a laser with a wavelength of 430 nm. Test samples are positioned within the evanescent decay distance from the bottom surface of the SIL using a closed- loop-controlled piezo actuator. The laser spot can be scanned over the sample enabling a study of the push-pull signal of pregrooved samples on a split photodiode. The intensity distribution and polarization state of the light reflected from the sample in the exit pupil of the microscope objective lens is studied on a CCD camera. The reflected light can be combined with a reference beam into an interferogram used for alignment purposes. We present measurements of evanescent coupling of light to a glass sample and the push-pull signal of a reflective phase grating with a groove pitch of 300 nm as a function of thickness of the air gap between de SIL and the sample. The evanescent coupling to a glass sample can accurately be described by thin-film optics theory. Experiments show that the push-pull signal amplitude depends on the polarization state of the irradiating beam.