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In the process of entangled optical quantum imaging, the Digital Micromirror Device (DMD) sampling mode affects imaging efficiency, and in the process of image sparse reconstruction, the use of a fixed sampling matrix affects the quality of image reconstruction. In this circumstance, this paper proposes an entangled optical quantum imaging method based on Adaptive Block Compressed Sampling with Two-Dimensional Information Entropy (ABCS-2DIE), which measures the texture details of the image through the two-dimensional information entropy of the image, adaptively allocates the sampling rate for each image block according to the texture distribution of the image, and designs the corresponding sampling matrix to sparsely sample the reference light. In addition, coincidence counting between the reference and signal light is considered in the reconstruction algorithm to obtain the target image. Experimental results show that compared with the Overall Compressive Sampling (OCS) method, the proposed method greatly shortens the imaging time and significantly improves the imaging quality. Besides, compared with the Fixed Block Compressed Sampling (FBCS) method, the image obtained by the proposed method has obvious improvement in visual effect, and the corresponding Peak Signal-to-Noise Ratio (PSNR) is improved by 2–4 dB with a slight increase in computation complexity. In all, the proposed method can make good use of the texture features of the image, effectively improving the quality of quantum imaging while reducing the imaging time. [ABSTRACT FROM AUTHOR]

During the process of scanning maskless lithography, exposure speed determines the efficiency and productivity of lithography fabrication. In this paper, a novel Digital Micromirror Device(DMD) based high-speed exposure method is proposed to optimize the exposure process and improve speed of scanning maskless lithography system. At first, structure and working principle of the DMD based maskless exposure system is presented. Then, fundamental principle of the proposed method is proposed. Exposure process of the proposed method and each module in the process including in scan stride pretreatment module, scan stride data storage module, high-speed real-time exposure image processing module and micromirror arrays control module are designed. Finally, the proposed method is implemented in the exposure experiment with TI DMD based scanning maskless lithography system and the results demonstrated the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper, based on the spatially and temporally resolved intensity and phase evaluation device: full information from a single hologram (STRIPED FISH), an improved single-frame full spatiotemporal field distribution measurement method is proposed. In our scheme, between diffractive optical element (DOE) and band-pass filter (BPF), and between BPF and the CCD camera, digital micromirror devices (DMD) are introduced to perfect the setup. Compared with the STRIPED FISH, our improved scheme can simultaneously improve the frame rate and maximize the utilization efficiency of the SBP of CCD. And simulation is carried out to demonstrate the process of the implementation, which confirmed the feasibility of the proposal. [ABSTRACT FROM AUTHOR]

Superposition of a Bessel beam with another beam was usually achieved using an Axicon or a SLM. Here we demonstrate a straightforward but powerful method to superpose a Bessel beam with another Bessel beam or a Gaussian beam based on a Digital Mirror Device (DMD). Different ring or circular patterns could be loaded in the DMD to generate Bessel beams or Gaussian beams respectively. By combining the ring and circular patterns, superposition of a Bessel beam with other Bessel beams or Gaussian beams could be achieved without using beam splitting or other complicated optical setups. The new DMD based Bessel beam superposition method could be easily controlled, quickly switched, or conveniently packed. [ABSTRACT FROM AUTHOR]

Due to the high penetrability of ultrasonic signals in scattering media, photoacoustic imaging based on photoacoustic effect is of great significance in the research of non-destructive testing and imaging of biological tissues. However, multiple light scattering will occur after the laser is incident on the scattering medium, resulting in poor imaging quality or inability to image. In this paper, we propose a novel method for wavefront shaping and photoacoustic imaging based on a photoacoustic transmission matrix. We use the photoacoustic transmission matrix method as the algorithm for wavefront shaping, and combine the superpixel method with a digital micromirror device (DMD) to modulate the amplitude and phase of the incident light, resulting in an enhancement factor of 10.75 for the photoacoustic signal. Then, we realize photoacoustic scanning imaging by moving the two-dimensional translation stage to drive the absorber above. Compared with the inability to image the initial photoacoustic signal before shaping, the shaped photoacoustic signal can obtain a clear photoacoustic image with a contrast ratio of 16.85. The wavefront shaping and photoacoustic imaging of photoacoustic signals based on photoacoustic transmission matrix method have a good prospect in the imaging of weaker photoacoustic signals. [ABSTRACT FROM AUTHOR]

The diffraction of an orbital angular momentum (OAM) beam behind slits and polygon apertures has enabled the measurement of light's topological charge (TC). In this work, we present a simple technique to measure higher TCs using Hadamard-coded apertures programmed in a digital micromirror device (DMD). Apart from pattern recognition, a common approach in relating the topological properties of the beam with its diffraction, we demonstrate that we can determine TCs from m = ± 1 to ± 10 using the position of diffracted intensity centroid R. We show thru experiments and simulations that indeed the centroids of the diffracted beams move depending on the magnitude and the sign of the TC, and the order N of the Hadamard aperture. Based on our results, distinguishing the TC of a beam is easier when | m | > 5. Lastly, we infer the source of the movement of the centroid using simple interference of three points derived from a Hadamard N = 2. By tracing the position of the zeroth-order maxima in the interference, we relate the maximum intensity position with the intensity centroid position in the diffraction. Our technique is crucial for determining higher-order modes whose TC are difficult to determine with the currently available methods. [ABSTRACT FROM AUTHOR]

Abstract: Maskless lithography (ML) provides a fast and low-cost method for projecting the images of IC or micro features onto photoresist. However, it needs an efficient simulation method to evaluate the performance of lithography process. In this paper, a pixel-based partially coherent image method for digital micro-mirror device (DMD) based ML is proposed based on the linear invariant theory. In our method, the mask is sampled by DMD pixel (each pixel corresponding to each micro-mirror) and expressed by rect function. Using the shift theory of Fourier transform and the stacked pupil operator approach, we build a matrix Φ for system response function of rect function. If the DMD pixel state matrix is S, then the aerial image can be calculated with two matrix multiplication I(x,y)= SΦ. [Copyright &y& Elsevier]

Abstract: A microelectromechanical system (MEMS) micromirror actuated by electrostatic repulsive force is demonstrated. The design is based on the principle that an asymmetric electric field produced by special layout of the electrodes can generate a repulsive force, which moves the mirror surface upwards. The factors affecting the magnitude of the driving force of the micromirror actuator are analyzed by FEA. The prototype is fabricated using a commercial available surface micromachining process and successfully tested using a Zygo NewView7300 interferometer. The displacement of the micromirror reaches 1.2μm at 60V. [Copyright &y& Elsevier]

The combination of three visible lasers with different wavelengths (Red/Green/Blue) illuminates a digital micro-mirror device (DMD) to generate color images, which is the core of a color imaging or display system. However, conventional optical configuration methods using a light-coupling combination produce the position mismatch of three images generated by DMDs because the diffraction angle of three wavelength beams is different. In this work, we propose a new color combination method using a separate secondary beam-combination structure (SSBCS) to achieve the complete mismatch of three images. The SSBCS can freely control the beam direction of a laser and the image shift is controllable, which can be used to compensate for the position mismatch of three images. Experiments indicate that the proposed method yields a high-quality combination of three images. The proposed methods can directly solve the color combination issue of three visible beams in an optical hardware aspect without the soft-compensation of the DMDs. [ABSTRACT FROM AUTHOR]

In this paper, a single pixel echelle spectrometer system based on compressed sensing theory is proposed. The Digital Micromirror Devices (DMD) is used as the Coding board, and the photomultiplier of high sensitivity point detector is used as the signal receiver. According to its structural characteristics, the optical system of the whole system is designed. The energy concentration of the spot in a single micro mirror can reach 70%. At the same time, the spectral information reconstruction algorithm is studied. Through the nonlinear recovery algorithm, when the compression factor is 20%, the original two-dimensional spectrum is reconstructed, and the two-dimensional spectrum is transformed into the required one-dimensional spectrum through the spectrum reduction algorithm. [ABSTRACT FROM AUTHOR]

We present spatial coherence measurements of partially coherent light in the far-field of incoherent sources with an experimental setup based on the Thompson–Wolf and Partanen–Turunen–Tervo experiments, to be performed in the context of a possible solar coherence measurement space instrument. The optical setup consists of a telescope to collimate light from a source, to diffract it by a digital micromirror device implementing a Young double-aperture interferometer in retroreflection mode, and finally to image the source into a two-dimensional sensor. Two multimode optical fibers with different diameters were used as incoherent sources and the results obtained for the spectral degree of coherence are compared to those expected from the van Cittert–Zernike theorem. [ABSTRACT FROM AUTHOR]

We present spatial coherence measurements of partially coherent light in the far-field of incoherent sources with an experimental setup based on the Thompson–Wolf and Partanen–Turunen–Tervo experiments, to be performed in the context of a possible solar coherence measurement space instrument. The optical setup consists of a telescope to collimate light from a source, to diffract it by a digital micromirror device implementing a Young double-aperture interferometer in retroreflection mode, and finally to image the source into a two-dimensional sensor. Two multimode optical fibers with different diameters were used as incoherent sources and the results obtained for the spectral degree of coherence are compared to those expected from the van Cittert–Zernike theorem. [ABSTRACT FROM AUTHOR]