Semantic segmentation with deep learning has achieved remarkable progress in classifying the pixels in the image. Acquiring sufficient ground-truth supervision to train deep visual models has been a bottleneck over the years due to the data-hungry nature of deep learning. Image-level label-based weakly supervised semantic segmentation (WSSS) aims to adopt image-level labels to train semantic segmentation models, saving vast human labors for costly pixel-level annotations. A typical pipeline for this problem is to adopt Class Activation Maps (CAMs) with image-level labels to generate pseudo-masks (a.k.a. seeds) and then use them for training segmentation models. The main difficulty is that seeds are usually sparse and incomplete. In recent years, GCNs have made great strides in various fields. GCN can perform global modeling and reasoning on the relationship between regions, which is beneficial for many computer vision tasks. This is our motivation to combine these two aspects. Therefore we propose the module of class-related graph convolution. Because there are differences between classes, our GCN is parallel. Each GCN can learn the classrelated region extension strategy. To enable GCN to learn more authentic relationships, we also introduce the attention mechanisms. We conduct lots of experiments on the public PASCAL VOC dataset, and our model yields state-of-the-art performance.
In this paper, we present the spatial beam modulator based on electrowetting liquid lens/prism array, in order to realize adjustment of various beams (parallel, convergent, divergent) in three-dimensional space. To calculating the adjustments range of the spatial beam modulator, the optical transfer function (OTF) is derived, according to the theories of geometrical optics, matrix optics and electrowetting. We also establish the simulation model for verifying the correctness of OTF by COMSOL. The results show that the spatial beam modulator can translate, expand, contract, converge and diverge the parallel beam. When the parallel beam is incident on the spatial beam modulator, the maximum translation distance of parallel beam is 0.92mm, and its focal length f can be adjusted in the range of 7.96 mm to ∞ (dual-convex liquid interface) or -∞ to 25.99 mm (dual-concave interface). In addition, the spatial beam modulator can also collimate, converge, diverge the convergent beam or divergence beam.
In this paper, an electrowetting-based prism-arrays system is proposed to be non-mechanical beam deflection controller in the three-dimensional space. The system is composed of five liquid prism units arranged at equal intervals in a cross shape. The relationship between beam deflection angle, electrowetting contact angle, and liquid refractive index are derived. The influence of electrowetting saturation, liquid refractive index, and interval between adjacent prisms on the performance of prism-arrays system are simulated in COMSOL, where the length and width of each prism are set to 3mm, and the height is set to 6mm. The shape of the liquid interface in liquid prism and its deflection are analyzed. The results show that the system succeed to achieve continuous control of beam deflection within a certain range, and the beam deflection angle of this arrayed liquid prisms is from -20° to 20° when 1-chloronaphthalene oil and 1% Nacl aqueous solution with sodium benzoate are filled in the liquid prisms. The smaller interval between adjacent prisms can increase the beam control range of the system. However, the liquid prism unit has a certain size, so the interval cannot be infinitely small. As the interval is set to 9mm, the steering region of the prism-arrays system is in a conical region with an apex angle of 40°, and the vertex of the circular cone is located at the 22.05mm in the z-axis. The proposed system will promote the development of nonmechanical beam deflection technology and have a wide range of applications.
The optical integrated aperture imaging system arranges several small aperture optical elements according to a certain regular spatial position, and achieves common phase precision on the same focal plane by adjusting the optical path and matching the phase. It is 0.1λ precision. As a high-precision displacement adjustment device, stacked piezoelectric ceramics can realize displacement deformation in the micrometer direction in the longitudinal direction. In this paper, a piezoelectric ceramic tube is stacked and filled with a transparent liquid medium. A compact optical phase modulator is designed and the output is prepared. Using interferometer to detect phase and combined with optimized image processing technology, an optical phase detection method with an accuracy of 0.1λ is obtained, which provides a feasible reference scheme for optical synthetic aperture common phase adjustment.
A novel optical scanning device based on electrowetting micro-prism (EMPs) is proposed, to solve the problems of beam
deflection controlling with laser line source . The basic beam control unit is made from EMPs, which including three
kinds of immiscible liquids (water / oil / water),whith utilizing electrowetting modulation of liquid contact angle in order
to mimic the refractive behavior for various classical prism geometries. Through the electro-wetting effect, the beam
deflection angle of the liquid prism can be adjusted about -15 ° ~ 15 °continuously in a specific voltage range (30 ~
110V).And compared to other electronic control deflection, this device has great deflection angle, whith exceeding the
continuous steering angles demonstrated for optical phased-array technology. At the same time, as the devices become
smaller in size ,its switching response speed can be much less than ms. This device will help us study robust Fresnel and
phased-array optics.
A novel device of dual-tuner variable-focus microlens consisting of three kinds of liquid is
put forward in this paper, whose basic structure includes a core chip sandwiched between two glass
covers. The core chip is made from electric conductor to simplify the device design and the fabrication
technics. The lens materials consist of three kinds of immiscible liquids, such as first conductive
liquids, insulating fluid and second conductive liquid with different refractive index. Two meniscuses
between every two liquids is used as optical lenses. The two-lens focal distances are tuned by changing
the curvature of these two meniscuses through the effect of electro-wetting. A new liquid microscope
based on EWOD is developed on the basis of the above mentioned structure, making achromatization
straightforward.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.