An ultra-fast focal reducer design originally intended for use with spherical primary mirrors (published in opticalengineering, February, 2003), has been adapted for use as a retro-fit for existing telescopes of simi...
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ISBN:
(纸本)0819454613
An ultra-fast focal reducer design originally intended for use with spherical primary mirrors (published in opticalengineering, February, 2003), has been adapted for use as a retro-fit for existing telescopes of similar to2m pupil diameter that have aspheric mirrors. The focal reducer has only one aspheric surface, located at the aperture stop, and can provide speeds up to f/0.75 while maintaining a wide field with pixel-limited resolution and a broad spectral passband. Examples have been computed for Ritchie-Chretien, Dall-Kirkham and Cassegrain systems, and for use at the prime focus of mirrors with non-zero conic constants.
Although hybrid (i.e. refractive-diffractive) surfaces are in common use in opticaldesign there are several phenomena which affect design MTF that are not routinely modeled in current commercial versions of optical d...
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ISBN:
(纸本)9780819468154
Although hybrid (i.e. refractive-diffractive) surfaces are in common use in opticaldesign there are several phenomena which affect design MTF that are not routinely modeled in current commercial versions of optical desig,n software. Typically the details of the diffractive structure are not taken into account and rays are traced through the hybrid surface employing a vector grating equation which uses the phase gradient associated with the diffractive definition to calculate a local grating spacing and orientation and from this grating information a 'diffracted ray' angle. This geometrical-optics based procedure has limitations;(I)it considers only the design diffraction order, (2)it does not take into account the sub-aperturing effect whereby color correction is reduced along, with zone count, and (3) the model used does not generate an exact blaze profile. In this paper we discuss progress in application of diffraction-based beam propagation tools in combination with a physical definition of the diffractive structure to more accurately model these secondary effects on design MTF. Results are given for some simple lenses and also the effects to be expected for a more complex zoom lens.
We have designed a light-guide for lighting applications, including automotive headlamps. The light-guide is designed based on a free-form slab. Our intention has been to optimize the design for creating legal pattern...
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ISBN:
(数字)9781510620629
ISBN:
(纸本)9781510620629
We have designed a light-guide for lighting applications, including automotive headlamps. The light-guide is designed based on a free-form slab. Our intention has been to optimize the design for creating legal patterns. One of our objectives has been to investigate how the changes in the shape of the freeform light-guide affects the light pattern, and how the light source geometry affects the design. For prototyping purpose, we use a particular polymer that exhibits optical performance close to acrylic (PMMA).
We demonstrate an iterative and inverse design of a segmented reflector used to illuminate the road with a uniform light distribution and reduced glare to the oncoming traffic. design is set to meet the StVZO standard...
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ISBN:
(数字)9781510644670
ISBN:
(纸本)9781510644670
We demonstrate an iterative and inverse design of a segmented reflector used to illuminate the road with a uniform light distribution and reduced glare to the oncoming traffic. design is set to meet the StVZO standard. The maximum brightness obtained is 1460 candela, which is five times brighter than a conventional headlamp of urban shared electric scooters and bicycles, resulting in improved visibility in dark environments. A prototype was built and tested at various environments. The tolerance analysis showed no negative influence on the desired standard light distribution. In addition to this iterative approach, a ray tracing code has been developed for inverse design and to map a desired uniform road illumination pattern back to the candela sensor for corresponding reflector design.
作者:
Robinson, DWNASA
Goddard Space Flight Ctr Greenbelt MD 20771 USA
A method of minimizing the optical distortion from gravity sag on a suspended large autocollimating flat mirror has been devised. This method consists of an inverted nine-point Hindle-Mount. A conventional Hindle-Moun...
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ISBN:
(纸本)0819437387
A method of minimizing the optical distortion from gravity sag on a suspended large autocollimating flat mirror has been devised. This method consists of an inverted nine-point Hindle-Mount. A conventional Hindle-Mount is located underneath a sky-viewing mirror and is primarily under compression loads from the weight of the mirror. It is not suitable for the situation where the mirror is viewing the ground, since a mirror would tend to fall out of the mount when in an inverted position. The inverted Hindle-Mount design consists of bonded joints on the backside of the mirror that allow the mirror to be held or suspended above an object to be viewed. This ability is useful in optical setups such as a calibration test where a flat mirror is located above a telescope so that the telescope may view a known optic.
Recently in the micro-opticalengineering area has been a grown in use of tunable liquid lenses because this lenses us allow versatility in the focusing range, also an easy handling and implementation. In the literatu...
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ISBN:
(纸本)9780819482822
Recently in the micro-opticalengineering area has been a grown in use of tunable liquid lenses because this lenses us allow versatility in the focusing range, also an easy handling and implementation. In the literature, many tunable lens models have been reported, but most of this work has been on describing the optical quality of the images, the opto-mechanical analysis is neglected. In this paper, an analysis of opto-mechanical of a tunable liquid lens is presented, for this;we show a finite element simulation of mechanical behavior and estimate how this influences in the optical performance of the lens. The liquid lens is composed of two elastic transparent membranes and of a cylindrical metallic mount.
This Volume 4767 of the conference proceedings contains 19 papers. Topics discussed include optical system, optical sensors, optical materials, opticaldesign and optical devices.
This Volume 4767 of the conference proceedings contains 19 papers. Topics discussed include optical system, optical sensors, optical materials, opticaldesign and optical devices.
In this work, two SMS algorithms are presented for an objective design with different selected ray-bundles: three meridian ray-bundles (3M) and one meridian and two skew ray-bundles (1M-2S), the latter from pin hole p...
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ISBN:
(纸本)9780819487384
In this work, two SMS algorithms are presented for an objective design with different selected ray-bundles: three meridian ray-bundles (3M) and one meridian and two skew ray-bundles (1M-2S), the latter from pin hole point of view, provides a better sampling of the phase space. Results obtained with different algorithms will be compared.
Consumers nowadays have a higher expectation on cameras beyond the function of taking photos or videos. In the early years, the applications of cameras with lenses were, however, very restricted. A new generation of s...
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ISBN:
(数字)9781510637719
ISBN:
(纸本)9781510637719
Consumers nowadays have a higher expectation on cameras beyond the function of taking photos or videos. In the early years, the applications of cameras with lenses were, however, very restricted. A new generation of super wide-angle lenses capture the user's surroundings in full 360 degrees, allowing the user's friends or families to step inside our universe and experience it, live. However, for such wide angle lens coverage, the relative illumination of the lens must take the vector nature of the light into account. Consequently, the polarization of light becomes a critical parameter. Custom coatings are commonly spread on the lens surface to avoid light transmission polarization falloff. But for consumer applications, complex coating is not a practical solution because it raises cost. In this paper, we present how to take care of the polarization during the design and analysis of the lensdesign. Additionally, design tips are proposed to suppress the polarization impact.
By using a binary phase grating, a lens centering system is constructed. In our system, the lens under alignment is mounted on a suitable mechanical axis that can be a spindle of precision lathe. A binary phase gratin...
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ISBN:
(纸本)0819437387
By using a binary phase grating, a lens centering system is constructed. In our system, the lens under alignment is mounted on a suitable mechanical axis that can be a spindle of precision lathe. A binary phase grating is used as a beam splitter. Laser beam after passing through the grating only +/- 1 orders are kept unstop, reflected back by lens surface, recombined by the same grating, and very good contrast interference fringes can be attained. When the lens together with the spindle is rotated, the interference fringes remain motionless only when the lens rotates around its axis of symmetry. If the lens rotates around an axis of asymmetry, the fringes will move. A CCD camera is used to monitor the fringes and transversal error less than a micrometer can be achieved. The interference fringes are very insensitive to vibration and environment. In the paper the theory are presented and the experimental results are given.
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