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Yichin Fang - One of the best experts on this subject based on the ideXlab platform.

  • Optical Design for Novel Glasses-Type 3D Wearable Ophthalmoscope
    MDPI AG, 2019
    Co-Authors: Chengmu Tsai, Yichin Fang, Tzu-chyang King, Nai-wie Hsueh, Che-wei Lin
    Abstract:

    This paper proposes a new Optical Design that will cooperate with 3D image technology, infrared spectrum technology, future medical diagnostics, the cloud, and big data analysis. We first conducted image recognition experiments to compare the pros and cons of 2D and 3D frameworks in order to make sure that the Optical and mechanical framework of a glasses-type 3D ophthalmoscope would be a better choice. The experimental results showed that a 3D image recognition rate (90%) was higher than a 2D image recognition rate (84%), and hence the 3D mechanism Design was selected. The glasses-type 3D ophthalmoscope Design is primarily based on the specification of indirect ophthalmoscope requirements and two working spectrums: a near infrared and a visible spectrum. The Design is a 2.5x magnification fixed focal telecentric relay system with a right-angle prism, which uses a large aperture to increase the amount of incident light (F/# = 2.0). As the infrared spectrums that have better transmittance towards human eye tissue are 965 nm and 985 nm, so that we took account of the visible spectrum and the near-infrared spectrum simultaneously to increase the basis of the physician’s diagnosis. In this research, we conclude that a wearable ophthalmoscope can be Designed Optically and mechanically with 3D technology, an infrared and a visible working spectrum and further, possibly in cooperation with the cloud and big data analysis

  • a study of Optical Design and optimization of zoom optics with liquid lenses through modified genetic algorithm
    Optics Express, 2011
    Co-Authors: Yichin Fang, Chengmu Tsai, Chenglun Chung
    Abstract:

    A new concept for the optimization and Optical Design of miniature digital zoom optics with liquid lens elements is proposed in this research. The liquid lens elements are limited to the discrete configuration in order to obtain the optimal performance for digital zoom. We propose a newly developed digital zoom layout and optimization with a modified genetic algorism (GA) method, in order to meet the demands of a certain specification. The results show that we achieve a successful Optical Design and the optimization of the digital zoom optics with liquid optics, whose performance is greatly improved up to 48.68%, from the standpoint of on-axis spot size.

  • Optical Design of automotive headlight system incorporating digital micromirror device
    Applied Optics, 2010
    Co-Authors: Chuancheng Hung, Bo Ren Hsueh, Yichin Fang, Mingshyan Huang, Shuanfu Wang, Bowen Wu, Weichi Lai, Yiliang Chen
    Abstract:

    In recent years, the popular adaptive front-lighting automobile headlight system has become a main emphasis of research that manufacturers will continue to focus great efforts on in the future. In this research we propose a new integral Optical Design for an automotive headlight system with an advanced light-emitting diode and digital micromirror device (DMD). Traditionally, automobile headlights have all been Designed as a low beam light module, whereas the high beam light module still requires using accessory lamps. In anticipation of this new concept of integral Optical Design, we have researched and Designed a single Optical system with high and low beam capabilities. To switch on and off the beams, a DMD is typically used. Because DMDs have the capability of redirecting incident light into a specific angle, they also determine the shape of the high or low light beam in order to match the standard of headlight illumination. With collocation of the multicurvature reflection lens Design, a DMD can control the light energy distribution and thereby reinforce the resolution of the light beam.

  • Optical Design and optimization of light emitting diode automotive head light with digital micromirror device light emitting diode
    Optik, 2010
    Co-Authors: Mingshyan Huang, Chuancheng Hung, Yichin Fang, Weichi Lai, Yiliang Chen
    Abstract:

    Abstract This research proposes a new method for light emitting diode automotive headlight Design with digital micromirror device (DMD). The Optical Design is advanced because of the following features. First, this Optical Design controls the angle of light pattern without light masking so as to achieve much higher light efficiency compared with traditional Optical Design for headlight systems. Second, in view of the tendency that the advanced light emitting diode automobile headlight is Designed to be a low beam light module and a high beam light still needs an auxiliary lighting system, the Optical system Designed in this research, mainly adopting DMD module as high/low beam light switch, can switch on and off both the high and low beam lights. Because DMDs function of accepting a bidimensional image, high/low beam light patterns can be determined by DMD. Third, a light pattern will be created and compensated simultaneously by DMD, which might replace mechanical adaptive front-lighting system in the future because DMD takes advantage of fast response and simultaneous compensation. Fourth, a Design using a multiple reflection curved mirror is employed in this research to adjust light energy distribution; therefore, the articulation of the light pattern can be enhanced. For this method, experimental results of light efficiency are up to 85%, which is superior to current products in the market.

Chenglun Chung - One of the best experts on this subject based on the ideXlab platform.

  • a study of Optical Design and optimization of zoom optics with liquid lenses through modified genetic algorithm
    Optics Express, 2011
    Co-Authors: Yichin Fang, Chengmu Tsai, Chenglun Chung
    Abstract:

    A new concept for the optimization and Optical Design of miniature digital zoom optics with liquid lens elements is proposed in this research. The liquid lens elements are limited to the discrete configuration in order to obtain the optimal performance for digital zoom. We propose a newly developed digital zoom layout and optimization with a modified genetic algorism (GA) method, in order to meet the demands of a certain specification. The results show that we achieve a successful Optical Design and the optimization of the digital zoom optics with liquid optics, whose performance is greatly improved up to 48.68%, from the standpoint of on-axis spot size.

L. Teriaca - One of the best experts on this subject based on the ideXlab platform.

  • Optical Design of the multi-wavelength imaging coronagraph Metis for the solar orbiter mission
    Experimental Astronomy, 2020
    Co-Authors: Silvano Fineschi, E Antonucci, G Nicolini, A M Malvezzi, G. Naletto, M. Romoli, V. Deppo, D. Moses, D. Spadaro, L. Teriaca
    Abstract:

    This paper describes the innovative Optical Design of the Metis coronagraph for the Solar Orbiter ESA-NASA mission. Metis is a multi-wavelength, externally occulted telescope for the imaging of the solar corona in both the visible and ultraviolet wavelength ranges. Metis adopts a novel occultation scheme for the solar disk, that we named “inverse external occulter”, for reducing the extremely high thermal load on the instrument at the spacecraft perihelion. The core of the Metis Optical Design is an aplanatic Gregorian telescope common to both the visible and ultraviolet channels. A suitable dichroic beam-splitter, optimized for transmitting a narrow-band in the ultraviolet (121.6 nm, HI Lyman-α) and reflecting a broadband in the visible (580–640 nm) spectral range, is used to separate the two Optical paths. Along the visible light Optical path, a liquid crystal electro-Optical modulator, used for the first time in space, allows making polarimetric measurements.

Silvano Fineschi - One of the best experts on this subject based on the ideXlab platform.

  • Optical Design of the multi-wavelength imaging coronagraph Metis for the solar orbiter mission
    Experimental Astronomy, 2020
    Co-Authors: Silvano Fineschi, E Antonucci, G Nicolini, A M Malvezzi, G. Naletto, M. Romoli, V. Deppo, D. Moses, D. Spadaro, L. Teriaca
    Abstract:

    This paper describes the innovative Optical Design of the Metis coronagraph for the Solar Orbiter ESA-NASA mission. Metis is a multi-wavelength, externally occulted telescope for the imaging of the solar corona in both the visible and ultraviolet wavelength ranges. Metis adopts a novel occultation scheme for the solar disk, that we named “inverse external occulter”, for reducing the extremely high thermal load on the instrument at the spacecraft perihelion. The core of the Metis Optical Design is an aplanatic Gregorian telescope common to both the visible and ultraviolet channels. A suitable dichroic beam-splitter, optimized for transmitting a narrow-band in the ultraviolet (121.6 nm, HI Lyman-α) and reflecting a broadband in the visible (580–640 nm) spectral range, is used to separate the two Optical paths. Along the visible light Optical path, a liquid crystal electro-Optical modulator, used for the first time in space, allows making polarimetric measurements.

  • novel space coronagraphs metis a flexible Optical Design for multi wavelength imaging and spectroscopy
    Proceedings of SPIE, 2013
    Co-Authors: Silvano Fineschi, Marco Romoli, Gerardo Capobianco, Giuseppe Crescenzio, G Massone, E Antonucci, A Bemporad, G Nicolini, D Telloni, Maurizio Focardi
    Abstract:

    This presentation outlines a general Optical Design for coronagraphs working in both the visible -light (VL) and UV /EUV wavelength ranges by combining the use of reflective , multilayer -coated or interference -coated optics with Lyot stops. This Design has been successfully applied to a sub -orbital coronagraph. Another version of this novel Design for visible -light/EUV coronagraphs uses an inverted -occultation Design in order to minimize the solar flux entering the instrument. This Design has been used for the coronagraph – METIS - on board the ESA Solar Orbital mission. T he current Optical configuration of METIS adopted for the Solar Orbiter mission includes Visible -light and UV imaging. However, the innovative inverted -occultation concept is flexible enough that it can also accommodate a EUV spectrograph ma intaining the same basic Optical layout. The paper also describes the potential capabilities of the inverted -occulter coronagraph as a VL/UV imager and EUV spectrograph for future solar mission s. Keywords: Solar instrumentation, Coronagraph y, UV imaging, UV Spectrography , visible -light polar imetry .

Koopman, Brian J. - One of the best experts on this subject based on the ideXlab platform.

  • The Optical Design of the six-meter CCAT-prime and Simons Observatory telescopes
    2018
    Co-Authors: Spyromilio Jason, Marshall, Heather K., Gilmozzi Roberto, Vavagiakis, Eve M., Stacey, Gordon J., Riechers, Dominik A., Mauskopf Philip, Matsuda, Frederick T., Limon Michele, Koopman, Brian J.
    Abstract:

    A common Optical Design for a coma-corrected, 6-meter aperture, crossed-Dragone telescope has been adopted for the CCAT-prime telescope of CCAT Observatory, Inc., and for the Large Aperture Telescope of the Simons Observatory. Both are to be built in the high altitude Atacama Desert in Chile for submillimeter and millimeter wavelength observations, respectively. The Design delivers a high throughput, relatively flat focal plane, with a field of view 7.8 degrees in diameter for 3 mm wavelengths, and the ability to illuminate >100k diffraction-limited beams for < 1 mm wavelengths. The optics consist of offset reflecting primary and secondary surfaces arranged in such a way as to satisfy the Mizuguchi-Dragone criterion, suppressing first-order astigmatism and maintaining high polarization purity. The surface shapes are perturbed from their standard conic forms in order to correct coma aberrations. We discuss the Optical Design, performance, and tolerancing sensitivity. More information about CCAT-prime can be found at ccatobservatory.org and about Simons Observatory at simonsobservatory.org

  • The Optical Design of the six-meter CCAT-prime and Simons Observatory telescopes
    'SPIE-Intl Soc Optical Eng', 2018
    Co-Authors: Parshley, Stephen C., Niemack, Michael D., Hills Richard, Dicker, Simon R., Dünner Rolando, Erler Jens, Gallardo, Patricio A., Gudmundsson, Jon E., Herter Terry, Koopman, Brian J.
    Abstract:

    A common Optical Design for a coma-corrected, 6-meter aperture, crossed-Dragone telescope has been adopted for the CCAT-prime telescope of CCAT Observatory, Inc., and for the Large Aperture Telescope of the Simons Observatory. Both are to be built in the high altitude Atacama Desert in Chile for submillimeter and millimeter wavelength observations, respectively. The Design delivers a high throughput, relatively flat focal plane, with a field of view 7.8 degrees in diameter for 3 mm wavelengths, and the ability to illuminate >100k diffraction-limited beams for < 1 mm wavelengths. The optics consist of offset reflecting primary and secondary surfaces arranged in such a way as to satisfy the Mizuguchi-Dragone criterion, suppressing first-order astigmatism and maintaining high polarization purity. The surface shapes are perturbed from their standard conic forms in order to correct coma aberrations. We discuss the Optical Design, performance, and tolerancing sensitivity. More information about CCAT-prime can be found at ccatobservatory.org and about Simons Observatory at simonsobservatory.org.Comment: Event: SPIE Astronomical Telescopes + Instrumentation, 2018, Austin, Texas, USA; Proceedings Volume 10700, Ground-based and Airborne Telescopes VII; 1070041 (2018