Microlenses fabricated using flexible elastomers can be tuned in focal length by application of controlled strain.By varying the strain azimuthally,the lenses may be deformed asymmetrically such that aberrations may b...Microlenses fabricated using flexible elastomers can be tuned in focal length by application of controlled strain.By varying the strain azimuthally,the lenses may be deformed asymmetrically such that aberrations may be controlled.This approach is used to tune the astigmatism of the tunable lenses,and it is shown that the generated wavefront may be accurately controlled.The lens presented here has an initial focal length of 32.6 mm and a tuning range of 12.3 mm for approximately 10%applied strain.The range of directly tunable Zernike polynomials representing astigmatism is about 3 mm,while the secondary lens errors,which cannot be tuned directly,vary only by about 0.2 mm.展开更多
We present the design,fabrication and characterization of hydraulically-tunable hyperchromatic lenses for two-dimensional(2D)spectrally-resolved spectral imaging.These hyperchromatic lenses,consisting of a positive di...We present the design,fabrication and characterization of hydraulically-tunable hyperchromatic lenses for two-dimensional(2D)spectrally-resolved spectral imaging.These hyperchromatic lenses,consisting of a positive diffractive lens and a tunable concave lens,are designed to have a large longitudinal chromatic dispersion and the images of different wavelengths from each other.2D objects of different wavelengths can consequently be imaged using the tunability of the lens system.Two hyperchromatic lens concepts are demonstrated and their spectral characteristics as well as their functionality in spectral imaging applications are shown.展开更多
The shape of liquid interfaces can be precisely controlled using electrowetting,an actuation mechanism which has been widely used for tunable optofluidic micro-optical components such as lenses or irises.We have expan...The shape of liquid interfaces can be precisely controlled using electrowetting,an actuation mechanism which has been widely used for tunable optofluidic micro-optical components such as lenses or irises.We have expanded the considerable flexibility inherent in electrowetting actuation to realize a variable optofluidic slit,a tunable and reconfigurable two-dimensional aperture with no mechanically moving parts.This optofluidic slit is formed by precisely controlled movement of the liquid interfaces of two highly opaque ink droplets.The 1.5mmlong slit aperture,with controllably variable discrete widths down to 45 mm,may be scanned across a length of 1.5mmwith switching times between adjacent slit positions of less than 120 ms.In addition,for a fixed slit aperture position,the width may be tuned to a minimum of 3 mmwith high uniformity and linearity over the entire slit length.This compact,purely fluidic device offers an electrically controlled aperture tuning range not achievable with extant mechanical alternatives of a similar size.展开更多
基金This work was funded by the German Science Foundation within the framework of the Priority Program 1337 Aktive MikrooptikThe authors thank Philipp Muller and the Laboratory for Biomedical Technology at IMTEK for coating the master lenses.
文摘Microlenses fabricated using flexible elastomers can be tuned in focal length by application of controlled strain.By varying the strain azimuthally,the lenses may be deformed asymmetrically such that aberrations may be controlled.This approach is used to tune the astigmatism of the tunable lenses,and it is shown that the generated wavefront may be accurately controlled.The lens presented here has an initial focal length of 32.6 mm and a tuning range of 12.3 mm for approximately 10%applied strain.The range of directly tunable Zernike polynomials representing astigmatism is about 3 mm,while the secondary lens errors,which cannot be tuned directly,vary only by about 0.2 mm.
基金This work was funded by the German Federal Ministry of Education and Research.
文摘We present the design,fabrication and characterization of hydraulically-tunable hyperchromatic lenses for two-dimensional(2D)spectrally-resolved spectral imaging.These hyperchromatic lenses,consisting of a positive diffractive lens and a tunable concave lens,are designed to have a large longitudinal chromatic dispersion and the images of different wavelengths from each other.2D objects of different wavelengths can consequently be imaged using the tunability of the lens system.Two hyperchromatic lens concepts are demonstrated and their spectral characteristics as well as their functionality in spectral imaging applications are shown.
基金funded by the German Research Foundation DFG within the Priority Program Active Micro-optics(SPP 1337).
文摘The shape of liquid interfaces can be precisely controlled using electrowetting,an actuation mechanism which has been widely used for tunable optofluidic micro-optical components such as lenses or irises.We have expanded the considerable flexibility inherent in electrowetting actuation to realize a variable optofluidic slit,a tunable and reconfigurable two-dimensional aperture with no mechanically moving parts.This optofluidic slit is formed by precisely controlled movement of the liquid interfaces of two highly opaque ink droplets.The 1.5mmlong slit aperture,with controllably variable discrete widths down to 45 mm,may be scanned across a length of 1.5mmwith switching times between adjacent slit positions of less than 120 ms.In addition,for a fixed slit aperture position,the width may be tuned to a minimum of 3 mmwith high uniformity and linearity over the entire slit length.This compact,purely fluidic device offers an electrically controlled aperture tuning range not achievable with extant mechanical alternatives of a similar size.
