Performance of optical interconnects using volume holographic gratings and substrate-guided waves is subject to source wavelength detuning which originates from laser chirping and operating temperature changes. In this letter, we characterize and measure the dispersion of commonly used surface-normal volume holographic gratings. Dispersion characteristics of a 20 mm thick photopolymer volume ho...

A miniaturized sensor head for the optical measurement of velocities of fluids based on laser Doppler velocimetry is demonstrated. Holographic optical elements mounted on a glass substrate are used for beam splitting and deflection. Volume holograms in dichromated gelatin exhibit good optical efficiency (75% transmission of a cascade of two holographic optical elements). With diffractive device...

Holographic optical tweezers use computer-generated holograms to create arbitrary three-dimensional configurations of single-beam optical traps that are useful for capturing, moving, and transforming mesoscopic objects. Through a combination of beam-splitting, mode-forming, and adaptive wavefront correction, holographic traps can exert precisely specified and characterized forces and torques on...

We present a new approach to obtain superresolved images in digital holography by means of synthetic aperture generation using common-path interferometry and off-axis illumination in optical imaging systems. The paper includes two parts. First, we present a simple approach to double the resolution of an optical system using tilted illumination onto the object and an optical element in the image...

Holography has been of increasing interest in recent years, with developments in many areas such as data storage and metrology. Photopolymer materials provide potentially good materials for holographic recording, as they are inexpensive and self-processing. Many experiments have been reported in the literature that describe the diffraction efficiency and angular selectivity of such materials. T...

Bowed with the weight of centuries he leans Upon his hoe and gazes upon the ground The emptiness of ages on his face And on his back the burden of the world Who will touch him Again with immortality Edward Markham "Man With a Hoe" Will it make a difference, world when I am gone? I think not. Who will ever shed a tear for me? 18 year-old female writing to Gisela Konopka Who will help adolescents...

A novel 2 x 2 polarization-independent optical switch with holographic optical elements is proposed. The switch consists of an electro-optic half-wave plate sandwiched between two pairs of holographic polarization beam splitters. Normally incident input and output couplings of this compact and lightweight device provide better flexibility and easier alignment for system applications.

Our objective is to enhance the effectiveness and efficiency of ad hoe and routing retrieval for large scale textbases. Effective retrieval means ranking relevant answer documents of a user's information need high on the output list. Our text processing and retrieval system PIRCS ( Probabilisitc Indexing and Retrieval -ComponentsSystem) handles English text in a domain independent fashion, and ...

ie over hashes Uiteraard dienen gebruikers en ontwikkelaars niet geconfron-teerd te worden met bestandsnamen met eerdergenoemde hashes. Dat is gelukkig ookniet het geval. Ze worden verborgen voor gebruikers door zogeheten user environmentsdie een verzameling “geactiveerde” componenten beschikbaar maken voor de gebruiker.User environments zijn zelf ook (automatisch gegenereerde) ...

We are all familiar with the phrase "beauty is in the eye of the beholder." In this case we have an instance of "the disease is in the eye of the beholder" which of course explains whY the cure is so elusive. The beholder rarely wants to do anything about it. To discuss this more subjectively, let's take a neutral case. Before doing so, we shall have to point out what a case can be expected to ...