Implementation of phase-shift patterns using a holographic projection system with phase-only diffractive optical elements

Author(s): Wei-Feng Hsu, Yu-Wen Chen, and Yuan-Hong Su Abstract: “We proposed a method to implement spatial phase-shift patterns with subdiffraction limited features through a holographic projection system. The input device of the system displayed phase-only diffractive optical elements that were calculated using the iterative Fourier-transform algorithm with the dummy-area method. By carefully designing the target patterns to the algorithm, the diffractive optical elements generated the Fourier-transformed images containing the phase-shift patterns in which the widths of dark lines were smaller than the diffraction limit. With these demonstrations, we have successfully shown that the near-field phase-shift lithographic technique can be realized…

The Applications and Technology of Phase-Only Liquid Crystal on Silicon Devices

Author(s): Collings, N.; Davey, T.; Christmas, J.; Chu, D.; Crossland, B. Abstract: “An introduction to the technology of liquid crystal on silicon (LCOS) devices leads on to a discussion of the application areas which have been and are being opened up by the development of phase-only devices.” Link to Publications Page Publication: Journal of Display Technology, (subscription required) Issue/Year/DOI: Journal of Display Technology, Vol. 7, Issue 3, pp. 112-119 (2010) doi:10.1109/JDT.2010.2049337

Speed-up of hologram generation using ClearSpeed Accelerator board

Author(s): Noriyuki Tanabe, Yasuyuki Ichihashi, Hirotaka Nakayama, Nobuyuki Masuda and Tomoyoshi Ito Abstract: “We have sped up the calculation of a computer-generated hologram by parallel computing using ClearSpeed Advance Dual CSX600 PCI-X Accelerator Board by ClearSpeed Technology plc. By using two boards in parallel, our system was able to perform the calculation 50 times as fast as a personal computer.” Link to Publications Page Publication: Computer Physics Communications – via ScienceDirect.com (subscription required) Issue/Year/DOI: Computer Physics Communications, Volume 180, Issue 10, October 2009, Pages 1870-1873 doi:10.1016/j.cpc.2009.06.001

Superhydrophobic surface structures in thermoplastic polymers by interference lithography and thermal imprinting

Author(s): Christian W.J. Berendsen, Marek Škereň, David Najdek and František Cerný Abstract: “We present a method to produce superhydrophobic surfaces in thermoplastic polymer substrates. The method involves the creation of a nickel stamp using a customized laser interference lithography technique and electroplating processes. This stamp is used to emboss sub-micrometer periodic structures into the thermoplastic. The modified surface is coated with a hydrophobic plasma-polymerized hexafluoropropene layer. Surfaces with different periodicity and relief depth were created. On the surface with the highest aspect ratio, advancing water contact angles of 167° were measured with a water contact angle hysteresis of below 5°.”…

A novel three-dimensional holographic display system based on LC-R2500 spatial light modulatora

Author(s): Huadong Zheng, Yingjie Yu, Cuixia Dai Abstract: “A novel holographic display system is proposed in this paper. The system takes LC-R2500, a kind of reflective liquid crystal spatial light modulator, (LC-SLM) as the core display unit, which can meet the requirement of real-time reconstruction of three-dimensional (3D) objects from holograms in free space. The relationship between hologram recording and image reconstruction is discussed, and the parameters associated with the magnification of reconstructed image over original object are determined. Experimental results of holographic display using the system are also given in the end.” Link to Publications Page Publication: Optik –…

Phase Contrast Projection Display Using Photopolymer

Author(s): Piao, Mei-Lan; Kim, Nam; Park, Jae-Hyeung Abstract: “We propose a phase contrast filter using photopolymer, for the phase contrast projection display. The photopolymer has high photosensitivity such that its optically induced refractive index change has a linear dependency on the illuminating light intensity. We implemented a phase contrast projection display using photopolymer as a phase contrast filter. By controlling the refractive index change of the photopolymer, we successfully convert an input phase image into a high contrast intensity image. We also investigated the effect of the photopolymer illumination condition on the quality of the displayed intensity image. As a…

Structured illumination in total internal reflection fluorescence microscopy using a spatial light modulator

Author(s): Reto Fiolka, Markus Beck, and Andreas Stemmer Abstract: “In wide-field fluorescence microscopy, illuminating the specimen with evanescent standing waves increases lateral resolution more than twofold. We report a versatile setup for standing-wave illumination in total internal reflection fluorescence microscopy. An adjustable diffraction grating written on a phase-only spatial light modulator controls the illumination field. Selecting appropriate diffraction orders and displaying a sheared (tilted) diffraction grating allows one to tune the penetration depth in very fine steps. The setup achieves 91 nm lateral resolution for green emission.” Link to Publications Page Publication: Optics Letters (subscription required) Issue/Year/DOI: Optics Letters, Vol….

A Projection System for Real World Three-Dimensional Objects Using Spatial Light Modulators

Author(s): Gopinathan, U. Monaghan, D.S. Hennelly, B.M. McElhinney, C.P. Kelly, D.P. McDonald, J.B. Naughton, T.J. Sheridan, J.T. Abstract: “We discuss a projection system for real world three-dimensional objects using spatial light modulators (SLM). An algorithm to encode the digital holograms of real world objects on to an SLM is presented. We present results from experiments to project holograms of real world holograms using a nematic liquid crystal SLM. We discuss the case when the pixel sizes of the charge-coupled device (CCD) and SLM used for recording the hologram and projection are different.” Link to Publications Page Publication: Journal of Display…

Projection display using computer-generated phase screens

Author(s): Neil Collings, Andreas Georgiou, Bill Crossland, and Jamie Christmas Abstract: “An approach to a robust and efficient projection display uses phasemodulating screens that reduce computer overhead.” Link to Publications Page Publication: SPIE Newsroom, (free download) Issue/Year/DOI: SPIE Newsroom, 26 February 2008, DOI: 10.1117/2.1200802.1015

An adaptive optics imaging system based on a high-resolution liquid crystal on silicon device

Author(s): Quanquan Mu, Zhaoliang Cao, Lifa Hu, Dayu Li, and Li Xuan Abstract: “An adaptive optics imaging system is introduced in this paper. A high resolution liquid crystal on silicon (LCOS) device was used as a phase only wave front corrector instead of a conversional deformable mirror. The wave front aberration was detected by a Shack-Hartmann (SH) wave front sensor, which has λ/100 rms wave front measurement accuracy. Under this construction 0.09λ (λ=0.6328µm) Peak to Valley correction precision was reached. Further more, some low frequency hot convection turbulence induced by an electric iron was compensated in real time at the…