SPIE Photonics Europe最新文献

{"title":"Singlet oxygen detection in water by means of digital holography and digital holographic tomography","authors":"A. Belashov, N. Petrov, I. Semenova, O. Vasyutinskii","doi":"10.1117/12.2227828","DOIUrl":"https://doi.org/10.1117/12.2227828","url":null,"abstract":"The paper presents results on singlet oxygen detection in aqueous solutions of a photosensitizer based on the reconstruction of 3D temperature gradients resulting from nonradiative deactivation of excited oxygen molecules. 3D temperature distributions were reconstructed by means of the inverse Abel transformation from a single digital hologram in the case of cylindrically symmetric distribution of the temperature gradient and using holographic tomography algorithm with filtered back projection in the case of nonsymmetrical distribution. Major features of the applied techniques are discussed and results obtained by the two methods are compared.","PeriodicalId":285152,"journal":{"name":"SPIE Photonics Europe","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133344389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A current-assisted CMOS photonic sampler with two taps for fluorescence lifetime sensing","authors":"H. Ingelberts, M. Kuijk","doi":"10.1117/12.2227819","DOIUrl":"https://doi.org/10.1117/12.2227819","url":null,"abstract":"Imaging based on fluorescence lifetime is becoming increasingly important in medical and biological applications. State-of- the-art fluorescence lifetime microscopes either use bulky and expensive gated image intensifiers coupled to a CCD or single-photon detectors in a slow scanning setup. Numerous attempts are being made to create compact, cost-effective all- CMOS imagers for fluorescence lifetime sensing. Single-photon avalanche diode (SPAD) imagers can have very good timing resolution and noise characteristics but have low detection efficiency. Another approach is to use CMOS imagers based on demodulation detectors. These imagers can be either very fast or very efficient but it remains a challenge to combine both characteristics. Recently we developed the current-assisted photonic sampler (CAPS) to tackle these problems and in this work, we present a new CAPS with two detection taps that can sample a fluorescence decay in two time windows. In the case of mono-exponential decays, two windows provide enough information to resolve the lifetime. We built an electro-optical setup to characterize the detector and use it for fluorescence lifetime measurements. It consists of a supercontinuum pulsed laser source, an optical system to focus light into the detector and picosecond timing electronics. We describe the structure and operation of the two-tap CAPS and provide basic characterization of the speed performance at multiple wavelengths in the visible and near-infrared spectrum. We also record fluorescence decays of different visible and NIR fluorescent dyes and provide different methods to resolve the fluorescence lifetime.","PeriodicalId":285152,"journal":{"name":"SPIE Photonics Europe","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131918784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Feedforward operation of a lens setup for large defocus and astigmatism correction","authors":"H. Verstraete, M. Almasian, P. Pozzi, R. Bilderbeek, J. Kalkman, D. Faber, M. Verhaegen","doi":"10.1117/12.2227111","DOIUrl":"https://doi.org/10.1117/12.2227111","url":null,"abstract":"In this manuscript, we present a lens setup for large defocus and astigmatism correction. A deformable defocus lens and two rotational cylindrical lenses are used to control the defocus and astigmatism. The setup is calibrated using a simple model that allows the calculation of the lens inputs so that a desired defocus and astigmatism are actuated on the eye. The setup is tested by determining the feedforward prediction error, imaging a resolution target, and removing introduced aberrations.","PeriodicalId":285152,"journal":{"name":"SPIE Photonics Europe","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132864380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nanoparticle scattering for multijunction solar cells","authors":"A. Mellor, N. P. Hylton, O. Höhn, C. Wellens, H. Hauser, T. Thomas, Y. Al-Saleh, N. Tucher, E. Oliva, B. Bläsi, N. Ekins‐Daukes, S. Maier","doi":"10.1117/12.2228589","DOIUrl":"https://doi.org/10.1117/12.2228589","url":null,"abstract":"We investigate the integration of Al nanoparticle arrays into the anti-reflection coatings (ARCs) of commercial triple-junction GaInP/ In0.01GaAs /Ge space solar cells, and study their effect on the radiation-hardness. It is postulated that the presence of nanoparticle arrays can improve the radiation-hardness of space solar cells by scattering incident photons obliquely into the device, causing charger carriers to be photogenerated closer to the junction, and hence improving the carrier collection efficiency in the irradiation-damaged subcells. The Al nanoparticle arrays were successfully embedded in the ARCs, over large areas, using nanoimprint lithography: a replication technique with the potential for high throughput and low cost. Irradiation testing showed that the presence of the nanoparticles did not improve the radiation-hardness of the solar cells, so the investigated structure has proven not to be ideal in this context. Nonetheless, this paper reports on the details and results of the nanofabrication to inform about future integration of alternative light-scattering structures into multi-junction solar cells or other optoelectronic devices.","PeriodicalId":285152,"journal":{"name":"SPIE Photonics Europe","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132869365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sinusoidal gratings for optimized light management in c-Si thin-film solar cells","authors":"K. Jäger, G. Köppel, C. Barth, M. Hammerschmidt, S. Herrmann, S. Burger, F. Schmidt, C. Becker","doi":"10.1117/12.2225459","DOIUrl":"https://doi.org/10.1117/12.2225459","url":null,"abstract":"Hexagonal sinusoidal nanotextures are well suited to couple light into silicon on glass at normal incidence, as we have shown in an earlier publication [K. Jäger et al., Opt. Express 24, A569 (2016)]. In this manuscript we discuss how these nanotextures perform under oblique incidence illumination. For this numerical study we use a rigorous solver for the Maxwell equations. We discuss nanotextures with periods between 350 nm and 730 nm and an aspect ratio of 0.5.","PeriodicalId":285152,"journal":{"name":"SPIE Photonics Europe","volume":"44 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132974342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of computational radiometric and spectral sensor calibration techniques","authors":"A. Manakov","doi":"10.1117/12.2228071","DOIUrl":"https://doi.org/10.1117/12.2228071","url":null,"abstract":"Radiometric and spectral calibration are essential for enabling the use of digital sensors for measurement purposes. Traditional optical calibration techniques require expensive equipment such as specialized light sources, monochromators, tunable filters, calibrated photo-diodes, etc. The trade-offs between computational and physics-based characterization schemes are, however, not well understood. In this paper we perform an analysis of existing computational calibration schemes and elucidate their weak points. We highlight the limitations by comparing against ground truth measurements performed in an optical characterization laboratory (EMVA 1288 standard). Based on our analysis, we present accurate and affordable methods for the radiometric and spectral calibration of a camera.","PeriodicalId":285152,"journal":{"name":"SPIE Photonics Europe","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133165670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electro-optic bandwidth manipulation of quantum light (Conference Presentation)","authors":"M. Karpiński, Michał Jachura, Laura J. Wright, Brian J. Smith","doi":"10.1117/12.2229232","DOIUrl":"https://doi.org/10.1117/12.2229232","url":null,"abstract":"Spectral-temporal manipulation of optical pulses has enabled numerous developments within a broad range of research topics, ranging from fundamental science to practical applications. Within quantum optics spectral-temporal degree of freedom of light offers a promising platform for integrated photonic quantum information processing. An important challenge in experimentally realizing spectral-temporal manipulation of quantum states of light is the need for highly efficient manipulation tools. In this context the intrinsically deterministic electro-optic methods show great promise for quantum applications. We experimentally demonstrate application of electro-optic platform for spectral-temporal manipulation of ultrashort pulsed quantum light. Using techniques analogous to serrodyne frequency shifting we show active spectral translation of few-picosecond single photon pulses by up to 0.5 THz. By employing an approach based on an electro-optic time lens we demonstrate up to 6-fold spectral compression of heralded single photon pulses with efficiency that enables us to significantly increase single photon flux through a narrow bandpass filter. We realize the required temporal phase manipulation by driving a lithium niobate waveguided electrooptic modulator with 33 dBm sinusoidal RF field at the frequency of either 10 GHz or 40 GHz. We use a phase lock loop to temporally lock the RF field to the 80 MHz repetition rate of approximately 1 ps long optical pulses. Heralded single photon wavepackets are generated by means of spontaneous parametric down-conversion in potassium dihydrogen phosphate (KDP) crystal, which enables preparation of spectrally pure single photon wavepackets without the need for spectral filtering. Spectral shifting is achieved by locking single-photon pulses to the linear slope of sinusoidal 40 GHz RF phase modulation. We verify the spectral shift by performing spectrally resolved heralded single photon counting, using frequency-to-time conversion by means of a highly dispersive chirped fiber Bragg grating. We verify the non-classicality of spectrally shifted single photons by measuring high-visibility Hong-Ou-Mandel interference using a reference single photon pulse. Spectral compression is based on the time lens principle, which requires locking optical pulses to approximately quadratic region of sinusoidal phase modulation. We utilize both 10 GHz and 40 GHz RF driving frequencies. Bandwidth compression is achieved by chirping the single photon pulse using an appropriate length of single-mode fibre and subsequently subjecting it to the action of the time lens. We verify spectral compression directly using the aforementioned spectrally-resolved heralded single photon counting method. We achieve 3-fold spectral compression of 2 nm bandwidth single photon pulses using 40 GHZ modulation frequency, and 6-fold spectral compression of 0.9 nm bandwidth single photon pulses using 10 GHz modulation frequency. Overall transmission of our set-","PeriodicalId":285152,"journal":{"name":"SPIE Photonics Europe","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121948944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accurate and high-performance 3D position measurement of fiducial marks by stereoscopic system for railway track inspection","authors":"A. A. Gorbachev, Mariya G. Serikova, E. N. Pantyushina, D. Volkova","doi":"10.1117/12.2228160","DOIUrl":"https://doi.org/10.1117/12.2228160","url":null,"abstract":"Modern demands for railway track measurements require high accuracy (about 2-5 mm) of rails placement along the track to ensure smooth, safe and fast transportation. As a mean for railways geometry measurements we suggest a stereoscopic system which measures 3D position of fiducial marks arranged along the track by image processing algorithms. The system accuracy was verified during laboratory tests by comparison with precise laser tracker indications. The accuracy of ±1.5 mm within a measurement volume 150×400×5000 mm was achieved during the tests. This confirmed that the stereoscopic system demonstrates good measurement accuracy and can be potentially used as fully automated mean for railway track inspection.","PeriodicalId":285152,"journal":{"name":"SPIE Photonics Europe","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125882406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Superresolution imaging system by color-coded tilted-beam illumination in digital in-line holographic microscopy","authors":"L. Granero, V. Micó, C. Ferreira, Z. Zalevsky, J. García","doi":"10.1117/12.2225590","DOIUrl":"https://doi.org/10.1117/12.2225590","url":null,"abstract":"Digital in-line holographic microscopy (DIHM) relates with the capability to achieve microscopic imaging working without lensless in the regime of holography. In essence, DIHM proposes a simple layout where a point source of coherent light illuminates the sample and the diffracted wavefront is recorded by a digital sensor. However, DIHM lacks high numerical aperture (NA) due to both geometrical distortion and the mandatory compromise between the illumination pinhole diameter, the illumination wavelength, and the need to obtain a reasonable light efficiency. One way to improve the resolution in DIHM, is by allowing superresolution imaging by angular multiplexing using tilted beam illumination. This illumination allows the on-axis diffraction of different spatial frequency content of the sample’s spectrum, different in comparison to the case when on-axis illumination is used. And after recover this additional spectral content, a synthetic numerical aperture (SNA) expanding up the cutoff frequency of the system in comparison with the on-axis illumination case can be assembled in a digital post-processing stage. In this contribution, we present a method to achieve one-dimensional (1-D) superresolved imaging in DIHM by a SINGLE SHOT illumination, using color-coded tilted beams. The method has been named as L-SESRIM (Lensless Single-Exposure Super-Resolved Interferometric Microscopy). Although the technique was previously presented showing very preliminary results [34], in this contribution we expand the experimental characterization (USAF resolution test target) as well as derive the theoretical frame for SNA generation using different illumination wavelengths.","PeriodicalId":285152,"journal":{"name":"SPIE Photonics Europe","volume":"209 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122652740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance prediction of optical image stabilizer using SVM for shaker-free production line","authors":"Hyung-Kwoun Kim, JungHyun Lee, Jin-Hee Hyun, Haekeun Lim, GyuYeol Kim, HyukSoo Moon","doi":"10.1117/12.2209001","DOIUrl":"https://doi.org/10.1117/12.2209001","url":null,"abstract":"Recent smartphones adapt the camera module with optical image stabilizer(OIS) to enhance imaging quality in handshaking conditions. However, compared to the non-OIS camera module, the cost for implementing the OIS module is still high. One reason is that the production line for the OIS camera module requires a highly precise shaker table in final test process, which increases the unit cost of the production. In this paper, we propose a framework for the OIS quality prediction that is trained with the support vector machine and following module characterizing features : noise spectral density of gyroscope, optically measured linearity and cross-axis movement of hall and actuator. The classifier was tested on an actual production line and resulted in 88% accuracy of recall rate.","PeriodicalId":285152,"journal":{"name":"SPIE Photonics Europe","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130722040","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}