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Thomas W. Stone

Bio: Thomas W. Stone is an academic researcher from University of Rochester. The author has contributed to research in topics: Achromatic lens & Diffraction efficiency. The author has an hindex of 7, co-authored 10 publications receiving 522 citations.

Papers
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Journal ArticleDOI
TL;DR: Hybrid elements containing optical power with both diffractive (holographic) and refractive components are shown to be useful for obtaining arbitrary or, in special cases, achromatic dispersive characteristics.
Abstract: Hybrid elements containing optical power with both diffractive (holographic) and refractive components are shown to be useful for obtaining arbitrary or, in special cases, achromatic dispersive characteristics. In one configuration a volume holographic element is coated on the surface of a crown glass lens, and by varying the power distributions among the refractive and holographic components while maintaining constant overall optical power the effective Abbe V numbers of the resultant hybrid element are shown to span all real numbers excepting a narrow interval around zero. In the achromat case (V number = ∞), both refractive and diffractive components are of the same sign resulting in much smaller glass curvatures than in all-refractive achromat doublets or apochromat triplets. The large separation between holographic partial dispersions and available glass partial dispersions is shown to lead to hybrid three-color achromats with greatly reduced glass curvatures. Applications are expected to include broadband achromatic objectives and chromatic aberration corrector plates in high performance optical systems. Such corrector plates may have any net power (including zero) while exhibiting effective V numbers that are positive or negative and that span a wide range, e.g., ±1 or ±1000. Further advantages include reducing the need for choosing high dispersion glasses, which may be costly and difficult to grind or polish. High diffraction efficiency and broad spectral bandwidths (in excess of 3000 A) are obtained in the holographic optical elements using single-element central-stop and cascaded element designs.

287 citations

Patent
01 May 1987
TL;DR: In this paper, a volume holographic elements (gratings) having geometries which tailor the spatio-temporal dispersion of the optical pulses for the system is presented.
Abstract: Optical systems, using volume holographic elements (gratings) having geometries which tailor the spatio-temporal dispersion of the optical pulses for the system. The input optical pulse is characterized by a frequency variation across the temporal profile of the pulse. The various frequency components of this pulse are first dispersed by at least one grating which may be of the blazed reflection or holographic volume transmission type. The resultant dispersed light is then diffracted by a holographic volume grating which imparts the desired temporal dispersion characteristics to the pulse. The shape of the holographic element will vary according to the input pulse frequency profile as formed by varied chirping techniques. A grating stage may then be repeated, preferably with additional elements in mirror symmetry to the first or by retro-reflection, in order to recombine the spatially dispersed pulse components into an exiting pulse which may be of vastly compressed temporal profile. In optical dispersive delay lines, the grating geometry provides temporal dispersion which is a desired function of wavelength of the optical pulses.

70 citations

Journal ArticleDOI
TL;DR: An experimental investigation of a passive pulse-shaping system capable of producing optical pulses of arbitrary temporal profile on the subnansecond time scale is described, and several results are included.
Abstract: A passive pulse-shaping system capable of producing optical pulses of arbitrary temporal profile on the subnansecond time scale is described and analyzed. The system uses a pair of gratings in a delay line and various filtering operations. An experimental investigation of the system is described, and several results are included.

64 citations

Patent
24 Oct 1986
TL;DR: In this paper, a volume transmission diffraction element is characterized by a periodic, spatial variation of refractive index or polarizability or other light transmission effecting parameter, and which is distributed throughout the volume of the element.
Abstract: An optical system which provides wavelength tuning and which may be a spectrometer, monochromator or tunable laser uses a volume transmission diffraction element which is characterized by a periodic, spatial variation of refractive index or polarizability or other light transmission effecting parameter, and which is distributed throughout the volume of the element. The wavelength is tuned by (1) varying the angles of the incident and diffracted light symmetrically with respect to the periodic distribution in the element and/or (2) by varying the spatial period of the diffracting element's volume modulation distribution which is maintained symmetric with respect to fixed incident and diffracted beam angles.

39 citations

Journal ArticleDOI
TL;DR: It is found that three- element cascades can exhibit spectral and field angle bandwidths essentially as broad as two-element cascades and that these bandwidths are in excess of 2300 A and 7° respectively.
Abstract: A comprehensive treatment is presented for the diffraction efficiencies of transmission holographic elements and cascade lenses when subject to broad spectral and field angle detunings. Experimental measurements are made in support of our theory on holographic optical elements fabricated in bleached silver-halide emulsions and in dichromated gelatin. The theory of holographic grating diffraction efficiency is studied through two approaches. A numerical treatment based on the theory of thin grating decomposition is implemented and shown to be in close agreement with other theories. Additionally, a more approximate approach is pursued in which the volume grating is treated as a phased array of scatterers. The latter approach leads to closed-form formulas in addition to a simple physical picture of volume effects. It is found that three-element cascades can exhibit spectral and field angle bandwidths essentially as broad as two-element cascades and that these bandwidths are in excess of 2300 A and 7° respectively.

37 citations


Cited by
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Journal ArticleDOI
01 May 1985
TL;DR: In this article, an exact formulation of the grating diffraction problem without approximations is presented, using a series of fundamental assumptions, which reduces to the various existing approximate theories in the appropriate limits.
Abstract: Diffraction characteristics of general dielectric planar (slab) gratings and surface-relief (corrugated) gratings are reviewed. Applications to laser-beam deflection, guidance, modulation, coupling, filtering, wavefront reconstruction, and distributed feedback in the fields of acoustooptics, integrated optics, holography, and spectral analysis are discussed. An exact formulation of the grating diffraction problem without approximations (rigorous coupled-wave theory developed by the authors) is presented. The method of solution is in terms of state variables and this is presented in detail. Then, using a series of fundamental assumptions, this rigorous theory is shown to reduce to the various existing approximate theories in the appropriate limits. The effects of these fundamental assumptions in the approximate theories are quantified and discussed.

989 citations

Journal ArticleDOI
TL;DR: In this article, the synthesis of arbitrarily shaped femtosecond pulses by spectral filtering in a temporally nondispersive grating apparatus is demonstrated by utilizing spatially patterned masks to modify the amplitude and the phase of the optical frequency components that are spatially dispersed within the apparatus.
Abstract: The synthesis of arbitrarily shaped femtosecond pulses by spectral filtering in a temporally nondispersive grating apparatus is demonstrated. Spectral filtering is accomplished by utilizing spatially patterned masks to modify the amplitude and the phase of the optical frequency components that are spatially dispersed within the apparatus. We are able to pattern spectra over a large dynamic range (approaching 104) and with unprecedented resolution. We illustrate the power of this technique by synthesizing a number of femtosecond waveforms, including femtosecond tone bursts with terahertz repetition rates, picosecond square pulses with 100-fsec rise times, and highly complex pseudonoise bursts produced by spectral phase encoding.

597 citations

Journal ArticleDOI
TL;DR: This paper summarizes the state-of-the-art in head-worn display design (HWD) and development and summarizes the results from previous design work using aspheric, diffractive, or holographic elements to achieve compact and lightweight systems.
Abstract: Head-worn display design is inherently an interdisciplinary subject fusing optical engineering, optical materials, optical coatings, electronics, manufacturing techniques, user interface design, computer science, human perception, and physiology for assessing these displays. This paper summarizes the state-of-the-art in head-worn display design (HWD) and development. This review is focused on the optical engineering aspects, divided into different sections to explore principles and applications. Building on the guiding fundamentals of optical design and engineering, the principles section includes a summary of microdisplay or laser sources, the Lagrange invariant for understanding the trade-offs in optical design of HWDs, modes of image presentation (i.e., monocular, biocular, and stereo) and operational modes such as optical and video see-through. A brief summary of the human visual system pertinent to the design of HWDs is provided. Two optical design forms, namely, pupil forming and non-pupil forming are discussed. We summarize the results from previous design work using aspheric, diffractive, or holographic elements to achieve compact and lightweight systems. The applications section is organized in terms of field of view requirements and presents a reasonable collection of past designs

529 citations

Journal ArticleDOI
TL;DR: In this article, the authors proposed an active and passive pulse shaping method based on phase-only filtering and an alternate Fourier synthesis pulse shaping technique, as well as additional passive and active pulse shaping methods.

482 citations

Journal ArticleDOI
TL;DR: The underlying physical principles of metasurface optical elements are introduced and, drawing on various works in the literature, how their constituent nanostructures can be designed with a highly customizable effective index of refraction that incorporates both phase and dispersion engineering are discussed.
Abstract: Control over the dispersion of the refractive index is essential to the performance of most modern optical systems. These range from laboratory microscopes to optical fibres and even consumer products, such as photography cameras. Conventional methods of engineering optical dispersion are based on altering material composition, but this process is time-consuming and difficult, and the resulting optical performance is often limited to a certain bandwidth. Recent advances in nanofabrication have led to high-quality metasurfaces with the potential to perform at a level comparable to their state-of-the-art refractive counterparts. In this Review, we introduce the underlying physical principles of metasurface optical elements (with a focus on metalenses) and, drawing on various works in the literature, discuss how their constituent nanostructures can be designed with a highly customizable effective index of refraction that incorporates both phase and dispersion engineering. These metasurfaces can serve as an essential component for achromatic optics with unprecedented levels of performance across a broad bandwidth or provide highly customized, engineered chromatic behaviour in instruments such as miniature aberration-corrected spectrometers. We identify some key areas in which these achromatic or dispersion-engineered metasurface optical elements could be useful and highlight some future challenges, as well as promising ways to overcome them. Flat metasurface optics provides an emerging platform for combining semiconductor foundry methods of manufacturing and assembling with nanophotonics to produce high-end and multifunctional optical elements. This Review highlights the design of metasurfaces, recent advances in the field and initial promising applications.

366 citations