Illuminating or imaging samples from a broad angular range is essential in a wide variety of computational 3D imaging and resolution-enhancement techniques, such as optical projection tomography, optical diffraction tomography, synthetic aperture microscopy, Fourier ptychographic microscopy, structured illumination microscopy, photogrammetry, and optical coherence refraction tomography. The wider the angular coverage, the better the resolution enhancement or 3D-resolving capabilities. However, achieving such angular ranges is a practical challenge, especially when approaching or beyond. Often, researchers resort to expensive, proprietary high numerical aperture (NA) objectives or to rotating the sample or source-detector pair, which sacrifices temporal resolution or perturbs the sample. Here, we propose several new strategies for multiangle imaging approaching 4pi steradians using concave parabolic or ellipsoidal mirrors and fast, low rotational inertia scanners, such as galvanometers. We derive theoretically and empirically relations between a variety of system parameters (e.g., NA, wavelength, focal length, telecentricity) and achievable fields of view (FOVs) and importantly show that intrinsic tilt aberrations donotrestrict FOV for many multiview imaging applications, contrary to conventional wisdom. Finally, we present strategies for avoiding spherical aberrations at obliquely illuminated flat boundaries. Our simple designs allow for high-speed multiangle imaging for microscopic, mesoscopic, and macroscopic applications.
more »
« less
Real-time wide-field spectral-scanning FMCW coherent 3D imaging and velocimetry
We present a real-time spectral-scanning frequency-modulated continuous wave (FMCW) 3D imaging and velocimetry system that can produce 3D depth maps at 33 Hz, with 48° × 68° field of view (FOV) and 32.8-cm depth range. Each depth map consists of 507 × 500 pixels, with 0.095° × 0.14° angular resolution and 2.82-mm depth resolution. The system employs a grating for beam steering and a telescope for angular FOV magnification. Quantitative depth, reflectivity, and axial velocity measurements of a static 3D printed depth variation target and a moving robotic arm are demonstrated.
more »
« less
- Award ID(s):
- 1902904
- PAR ID:
- 10389162
- Date Published:
- Journal Name:
- Optics Letters
- Volume:
- 47
- Issue:
- 16
- ISSN:
- 0146-9592
- Page Range / eLocation ID:
- 4064
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
Mask-based integrated fluorescence microscopy is a compact imaging technique for biomedical research. It can perform snapshot 3D imaging through a thin optical mask with a scalable field of view (FOV) and a thin device thickness. Integrated microscopy uses computational algorithms for object reconstruction, but efficient reconstruction algorithms for large-scale data have been lacking. Here, we developed DeepInMiniscope, a miniaturized integrated microscope featuring a custom-designed optical mask and a multi-stage physics-informed deep learning model. This reduces the computational resource demands by orders of magnitude and facilitates fast reconstruction. Our deep learning algorithm can reconstruct object volumes over 4×6×0.6 mm3. We demonstrated substantial improvement in both reconstruction quality and speed compared to traditional methods for large-scale data. Notably, we imaged neuronal activity with near-cellular resolution in awake mouse cortex, representing a substantial leap over existing integrated microscopes. DeepInMiniscope holds great promise for scalable, large-FOV, high-speed, 3D imaging applications with compact device footprint. # DeepInMiniscope: Deep-learning-powered physics-informed integrated miniscope [https://doi.org/10.5061/dryad.6t1g1jx83](https://doi.org/10.5061/dryad.6t1g1jx83) ## Description of the data and file structure ### DeepInMiniscope: Learned Integrated Miniscope ### Datasets, models and codes for 2D and 3D sample reconstructions. Dataset for 2D reconstruction includes test data for green stained lens tissue. Input: measured images of green fluorescent stained lens tissue, dissembled into sub-FOV patches. Output: the slide containing green lens tissue features. Dataset for 3D sample reconstructions includes test data for 3D reconstruction of in-vivo mouse brain video recording. Input: Time-series standard-derivation of difference-to-local-mean weighted raw video. Output: reconstructed 4-D volumetric video containing a 3-dimensional distribution of neural activities. ## Files and variables ### Download data, code, and sample results 1. Download data `data.zip`, code `code.zip`, results `results.zip`. 2. Unzip the downloaded files and place them in the same main folder. 3. Confirm that the main folder contains three subfolders: `data`, `code`, and `results`. Inside the `data` and `code` folder, there should be subfolders for each test case. ## Data 2D_lenstissue **data_2d_lenstissue.mat:** Measured images of green fluorescent stained lens tissue, disassembled into sub-FOV patches. * **Xt:** stacked 108 FOVs of measured image, each centered at one microlens unit with 720 x 720 pixels. Data dimension in order of (batch, height, width, FOV). * **Yt:** placeholder variable for reconstructed object, each centered at corresponding microlens unit, with 180 x 180 voxels. Data dimension in order of (batch, height, width, FOV). **reconM_0308:** Trained Multi-FOV ADMM-Net model for 2D lens tissue reconstruction. **gen_lenstissue.mat:** Generated lens tissue reconstruction by running the model with code **2D_lenstissue.py** * **generated_images:** stacked 108 reconstructed FOVs of lens tissue sample by multi-FOV ADMM-Net, the assembled full sample reconstruction is shown in results/2D_lenstissue_reconstruction.png 3D_mouse **reconM_g704_z5_v4:** Trained 3D Multi-FOV ADMM-Net model for 3D sample reconstructions **t_img_recd_video0003 24-04-04 18-31-11_abetterrecordlong_03560_1_290.mat:** Time-series standard-deviation of difference-to-local-mean weighted raw video. * **Xts:** test video with 290 frames and each frame 6 FOVs, with 1408 x 1408 pixels per FOV. Data dimension in order of (frames, height, width, FOV). **gen_img_recd_video0003 24-04-04 18-31-11_abetterrecordlong_03560_1_290_v4.mat:** Generated 4D volumetric video containing 3-dimensional distribution of neural activities. * **generated_images_fu:** frame-by-frame 3D reconstruction of recorded video in uint8 format. Data dimension in order of (batch, FOV, height, width, depth). Each frame contains 6 FOVs, and each FOV has 13 reconstruction depths with 416 x 416 voxels per depth. Variables inside saved model subfolders (reconM_0308 and reconM_g704_z5_v4): * **saved_model.pb:** model computation graph including architecture and input/output definitions. * **keras_metadata.pb:** Keras metadata for the saved model, including model class, training configuration, and custom objects. * **assets:** external files for custom assets loaded during model training/inference. This folder is empty, as the model does not use custom assets. * **variables.data-00000-of-00001:** numerical values of model weights and parameters. * **variables.index:** index file that maps variable names to weight locations in .data. ## Code/software ### Set up the Python environment 1. Download and install the [Anaconda distribution](https://www.anaconda.com/download). 2. The code was tested with the following packages * python=3.9.7 * tensorflow=2.7.0 * keras=2.7.0 * matplotlib=3.4.3 * scipy=1.7.1 ## Code **2D_lenstissue.py:** Python code for Multi-FOV ADMM-Net model to generate reconstruction results. The function of each script section is described at the beginning of each section. **lenstissue_2D.m:** Matlab code to display the generated image and reassemble sub-FOV patches. **sup_psf.m:** Matlab script to load microlens coordinates data and to generate PSF pattern. **lenscoordinates.xls:** Microlens units coordinates table. **3D mouse.py:** Python code for Multi-FOV ADMM-Net model to generate reconstruction results. The function of each script section is described at the beginning of each section. **mouse_3D.m:** Matlab code to display the reconstructed neural activity video and to calculate temporal correlation. ## Access information Other publicly accessible locations of the data: * [https://github.com/Yang-Research-Laboratory/DeepInMiniscope-Learned-Integrated-Miniscope](https://github.com/Yang-Research-Laboratory/DeepInMiniscope-Learned-Integrated-Miniscope)more » « less
-
Holography is a promising avenue for high-quality displays without requiring bulky, complex optical systems. While recent work has demonstrated accurate hologram generation of 2D scenes, high-quality holographic projections of 3D scenes has been out of reach until now. Existing multiplane 3D holography approaches fail to model wavefronts in the presence of partial occlusion while holographic stereogram methods have to make a fundamental tradeoff between spatial and angular resolution. In addition, existing 3D holographic display methods rely on heuristic encoding of complex amplitude into phase-only pixels which results in holograms with severe artifacts. Fundamental limitations of the input representation, wavefront modeling, and optimization methods prohibit artifact-free 3D holographic projections in today’s displays. To lift these limitations, we introduce hogel-free holography which optimizes for true 3D holograms, supporting both depth- and view-dependent effects for the first time. Our approach overcomes the fundamental spatio-angular resolution tradeoff typical to stereogram approaches. Moreover, it avoids heuristic encoding schemes to achieve high image fidelity over a 3D volume. We validate that the proposed method achieves 10 dB PSNR improvement on simulated holographic reconstructions. We also validate our approach on an experimental prototype with accurate parallax and depth focus effects.more » « less
-
Near-eye display systems for augmented reality (AR) aim to seamlessly merge virtual content with the user’s view of the real-world. A substantial limitation of current systems is that they only present virtual content over a limited portion of the user’s natural field of view (FOV). This limitation reduces the immersion and utility of these systems. Thus, it is essential to quantify FOV coverage in AR systems and understand how to maximize it. It is straightforward to determine the FOV coverage for monocular AR systems based on the system architecture. However, stereoscopic AR systems that present 3D virtual content create a more complicated scenario because the two eyes’ views do not always completely overlap. The introduction of partial binocular overlap in stereoscopic systems can potentially expand the perceived horizontal FOV coverage, but it can also introduce perceptual nonuniformity artifacts. In this arrticle, we first review the principles of binocular FOV overlap for natural vision and for stereoscopic display systems. We report the results of a set of perceptual studies that examine how different amounts and types of horizontal binocular overlap in stereoscopic AR systems influence the perception of nonuniformity across the FOV. We then describe how to quantify the horizontal FOV in stereoscopic AR when taking 3D content into account. We show that all stereoscopic AR systems result in a variable horizontal FOV coverage and variable amounts of binocular overlap depending on fixation distance. Taken together, these results provide a framework for optimizing perceived FOV coverage and minimizing perceptual artifacts in stereoscopic AR systems for different use cases.more » « less
-
Mask-based integrated fluorescence microscopy is a compact imaging technique for biomedical research. It can perform snapshot 3D imaging through a thin optical mask with a scalable field of view (FOV). Integrated microscopy uses computational algorithms for object reconstruction, but efficient reconstruction algorithms for large-scale data have been lacking. Here, we developed DeepInMiniscope, a miniaturized integrated microscope featuring a custom-designed optical mask and an efficient physics-informed deep learning model that markedly reduces computational demand. Parts of the 3D object can be individually reconstructed and combined. Our deep learning algorithm can reconstruct object volumes over 4 millimeters by 6 millimeters by 0.6 millimeters. We demonstrated substantial improvement in both reconstruction quality and speed compared to traditional methods for large-scale data. Notably, we imaged neuronal activity with near-cellular resolution in awake mouse cortex, representing a substantial leap over existing integrated microscopes. DeepInMiniscope holds great promise for scalable, large-FOV, high-speed, 3D imaging applications with compact device footprint.more » « less
An official website of the United States government

