We present an optically addressed non-pixelated spatial light modulator. The system is based on reversible photoalignment of a LC cell using a red light sensitive novel azobenzene photoalignment layer. It is an electrode-free device that manipulates the liquid crystal orientation and consequently the polarization via light without artifacts caused by electrodes. The capability to miniaturize the spatial light modulator allows the integration into a microscope objective. This includes a miniaturized 200 channel optical addressing system based on a VCSEL array and hybrid refractive-diffractive beam shapers. As an application example, the utilization as a microscope objective integrated analog phase contrast modulator is shown.

We report on a single-stage high-power amplification of a radially polarized mode-locked laser beam in a single-crystal fiber (SCF) amplifier. The seed beam was amplified by a factor of 5.0 to an average output power of 66.3 W. The pulse duration of the amplified pulses was measured to be 909 fs at a repetition rate of 40.7 MHz, corresponding to a pulse energy of 1.63 \(\upmu\)J and a resulting pulse peak power of 1.58 MW. The output beam showed a very high quality of the doughnut-shaped intensity distribution and furthermore a high radial polarization purity.

We report on the first demonstration of a radially polarized passively mode-locked thin-disk oscillator. Radial polarization was achieved by the use of a novel circular grating waveguide output coupler. We showed mode-locked operation up to a maximum average output power of 13.3 W with an optical efficiency of 21.8%. The degree of radial polarization of the emitted beam was measured to be 97±1%. The laser system generated pulses with a duration of 907 fs and an energy of 316 nJ corresponding to a peak power of 0.35 MW. To the best of our knowledge, these values exceed the performance of previously reported radially polarized mode-locked oscillator systems.

How accurately can you determine positions using a non-expensive imaging system? We demonstrate a system, that has the potential to achieve position detections over a large measurement field (200 x 200 mm) for one million times one million 2D positions. Non-expensive telecentric imaging of the large object field is achieved using a large diffractive front element in combination with two small off-the-shelf lenses. The position measurement itself is considerably improved using a simple replication technique: the point to be measured is replicated N-times and the centers of gravity of the N points are averaged. By this approach discretization errors and camera noise are reduced by the square root of the number of points. We describe the system, discuss the error model and show experimental results for the DOE-based telecentric imaging and the position detection sensing.

We present a device for tunable spatial polarization shaping, based on a red light photo-addressable cell. Such a cell compartment is based on a bisazobenzene containing photoaligning layer and a rubbed PI aligning and is filled with the LC mixture E5. Switchable spatial addressing patterns are generated by a 200 channel micro optical addressing unit based on a red VCSEL array (lambda = 650 nm) and diffractive beam shapers.

Diffractive optical elements offer a high degree of freedom for controlling phase and spectral behavior in optical designs. This enables new and compact optical sensors and measurement systems. We show several recent applications which bene t from unique properties of diffractive optical elements. The applications include: field aberration correction e.g. for microscopic projection applications through microscope objective lenses, a 200 channel microscope objective integrated optical addressing system, diffractive/refractive hybrid optics for high efficiency beam shaping and deflection angle enlargement of spatial light modulators.

Passive and active polarization elements were created by surface and bulk photo-alignment of LCs, reactive LCs, photo-sensitive LCP and photo-curable monomer/LC composites. The use of different photo-sensitive liquid crystalline materials for the development of highly anisotropic elements with high spatial resolution and stability or, alternatively, fast switch ability will be discussed. Photo-active and voltage tunable polarization and diffraction elements are presented. For active micro-optic application a photo-addressed patterned retarder was created. Electrically switchable diffraction gratings were generated by interference exposure of photo-curable LC composites at room temperature characterized by droplet free morphology. These polarization sensitive diffraction elements are characterized be excellent optical properties and low switching times.

Microoptical components play an increasing role in different technology fields such as medical engineering, materials and information processing, imaging and metrology. But their realization needs the combination of modern design concepts with sophisticated processing technologies, new materials and design tools. Furthermore, the introduction of ambitious processing technologies must be accompanied by effective metrology and inspection tools. Therefore, this paper reports about the technologies for making microoptics at ITO. Because sophisticated measurement tools are an indispensable part of the fabrication process, the paper describes our multi-scale inspection approach for the testing of microstructures on wafer-scale level. Finally, some representative applications of microoptical components for advanced measurement and imaging are explained.

We investigate the possibility to produce photochromic CGHs with maskless lithography methods. For this purpose, optical properties and requirements of photochromic materials will be shown. A diarylethene-based polyurethane is developed and characterized. The resolution limit and the influence of the writing parameters on the produced patterns, namely speed rate and light power, have been determined. After the optimization of the writing process, gratings and Fresnel Zone Plates are produced on the photochromic layer and diffraction efficiencies are measured. Improvements and perspectives will be discussed.

We present a detailed analysis of the transverse beam profile and the polarization characteristics of red-emitting oxide-confined vertical-cavity surface- emitting lasers (VCSELs). We demonstrate that oxide aperture sizes smaller than 6 mu m are required for emission in fundamental mode. We further show first steps towards integrating beam shaping optics directly into the top mirror of the VCSEL.

In this contribution some conceptual considerations regarding the implementation of optical sensors for process control will be given. Therefore first a classification of monitoring systems related to the level of process integration is made. In a second step there will be a description of relevant features for the characterization of the process state. Furthermore there a description of factors resulting from the machining process that have possibly an impact upon the measurement result is given.As an exemplary implementation of an optical sensor near the machining process a concept for a robust and miniaturized sensor probe based on chromatic confocal microscopy with gradient index (GRIN) lenses will be presented.

Real-time high-throughput identification, screening, characterization, and processing of biological specimen is of great interest to a host of areas spanning from cell biology and medicine to security and defense. Much like human biometrics, microorganisms exhibit natural signatures that can be used for identification. In this paper, we first overview two optical techniques, namely digital holographic microscopy and holographic optical tweezers which can non-invasively image, manipulate, and identify microorganisms in three dimensions. The two methods bear similarities in their optics and implementation. Thus, we have proposed a new approach to identification of micro/nano organisms and cells by combining the two methods of digital holographic microscopy and holographic optical tweezers which can be integrated into a single compact hardware. The proposed system can simultaneously sense, control, identify, and track cells and microorganisms in three dimensions. New possibilities that arise from the proposed method are discussed.

In this paper we present a novel technique for steering the beam of a scanning laser-Doppler vibrometer (LDV) using a Spatial Light Modulator (SLM). Computer Generated Holograms (CGH) are employed to obtain the phase maps displayed by the SLM. Due to this approach, spurious diffraction orders are generated. We present concepts to suppress these diffraction orders so as to realize a scanning vibrometer. We discuss the properties and limitations of this solution. Different SLMs have been evalutated and a compact scanning vibrometer based on a Holoeye Pluto SLM has been realized. First measurement results are presented. In addition, we demonstrate simulations on the reduction of speckle related signal dropouts. Drop-Outs can be reduced by adapting the measurement-beam wavefront with the CGH to maximize the light power collected with the vibrometer aperture. We have explored an approach to optimize the signal strength by adapting the coefficients of the Zernike polynomials of an additional wavefront shift.

We introduce a method for marker-free cell discrimination based on optical tweezers.Cancerous, non-cancerous, and drug-treated cells could be distinguished by measuring the trapping forces using holographic optical tweezers.We present trapping force measurements on different cell lines: normal pre-B lymphocyte cells (BaF3; "normal cells"), their Bcr-Abl transformed counterparts (BaF3-p185; "cancer cells") as a model for chronic myeloid leukaemia (CML) and Imatinib treated BaF3-p185 cells.The results are compared with reference measurements obtained by a commercial flow cytometry system.

Archiv der PharmazieVolume 275, Issue 8 p. 557-570 Wissenschaftlicher Teil Über die Amyrine H. Dieterle, H. Dieterle Pharmazeutischen Institut der Johann-Wolfgang-Goethe-Universität, Frankfurt a. M.Search for more papers by this authorH. Braß, H. Braß Pharmazeutischen Institut der Johann-Wolfgang-Goethe-Universität, Frankfurt a. M.Search for more papers by this authorF. Schaal, F. Schaal Pharmazeutischen Institut der Johann-Wolfgang-Goethe-Universität, Frankfurt a. M.Search for more papers by this author H. Dieterle, H. Dieterle Pharmazeutischen Institut der Johann-Wolfgang-Goethe-Universität, Frankfurt a. M.Search for more papers by this authorH. Braß, H. Braß Pharmazeutischen Institut der Johann-Wolfgang-Goethe-Universität, Frankfurt a. M.Search for more papers by this authorF. Schaal, F. Schaal Pharmazeutischen Institut der Johann-Wolfgang-Goethe-Universität, Frankfurt a. M.Search for more papers by this author First published: 1937 https://doi.org/10.1002/ardp.19372750802Citations: 5AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume275, Issue81937Pages 557-570 RelatedInformation