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1.
Genome Biol ; 25(1): 149, 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38845006

ABSTRACT

Cancer is a complex disease composing systemic alterations in multiple scales. In this study, we develop the Tumor Multi-Omics pre-trained Network (TMO-Net) that integrates multi-omics pan-cancer datasets for model pre-training, facilitating cross-omics interactions and enabling joint representation learning and incomplete omics inference. This model enhances multi-omics sample representation and empowers various downstream oncology tasks with incomplete multi-omics datasets. By employing interpretable learning, we characterize the contributions of distinct omics features to clinical outcomes. The TMO-Net model serves as a versatile framework for cross-modal multi-omics learning in oncology, paving the way for tumor omics-specific foundation models.


Subject(s)
Neoplasms , Humans , Neoplasms/genetics , Genomics , Medical Oncology , Machine Learning , Multiomics
2.
Appl Opt ; 61(18): 5449-5456, 2022 Jun 20.
Article in English | MEDLINE | ID: mdl-36256112

ABSTRACT

Allowing natural scenes as well as maximizing field of view (FoV) can benefit from the minimization of distortion for the wide-angle camera. The wide-angle camera utilizing freeform surfaces for mitigating distortions, either barrel distortion or pincushion distortion, is therefore of interest. In this paper, the designs of using all-aspherical surfaces and aspherical surfaces combined with freeform surfaces are investigated. To minimize the deviation before and after converting from aspherical surfaces to freeform surfaces, a mathematical conversion scheme is derived. By applying it to the design example, the methodology is shown to be effective in the case of an optical system with a large number of aspherical/freeform surfaces. Additionally, custom freeform analysis tools are developed for quantitative analysis and visualization of the critical characteristics of optical performance, namely, a 2D lateral color field map, 2D relative illumination field map, 2D spot radius field map, and 2D average modulation transfer function (MTF) field map. Compared to classical all-aspherical design, simulation results show that freeform design has the capability to reduce distortion, and other performances such as relative illumination, spot size, and MTF can also be improved, even though there are some compromises on the peripheral FoV. The design approach will have potential important research and application values for lens systems utilized in miniature camera lenses, especially the wide FoV capability.

3.
Appl Opt ; 59(27): 8408-8417, 2020 Sep 20.
Article in English | MEDLINE | ID: mdl-32976428

ABSTRACT

In addition to utilizing traditional aspheric surfaces, complicated geometric curves for meeting stringent design requirements can also be adopted in optical systems. In this paper, we investigate two geometric shape modeling schemes, namely, pedal and cosine curves, which allow for representation of an S-shaped profile for the optical design of a camera lens. To obtain a powerful tool for representing a quasi-aspheric surface (QAS) to resemble the designed form surface, we linearly combine the pedal/cosine function with a base conic section. The detailed parameterization process of representation is discussed in this paper. Subsequently, an existing starting point that has similar specifications to that of the design requirements is selected. During the optimization process, a least-squares fitting algorithm is implemented to obtain the optimal coefficient values of the proposed QAS representation, and then the parameters (radii, air thickness, lens thickness, coefficients, materials, etc.) of the optical system are set to optimize the optical performance, gradually aiming to minimize the predefined merit function. We demonstrate the applicability of the proposed geometric modeling schemes via two design examples. In comparison to a conventional aspheric camera lens of the same specifications, the optical performance with respect to field of view and distortion has been improved due to higher degrees of design freedom. We believe that the proposed technology of geometric modeling schemes promises to improve optical performance due to these higher degrees of freedom and appears to be applicable to many different camera lenses.

4.
Appl Opt ; 57(16): 4457-4466, 2018 Jun 01.
Article in English | MEDLINE | ID: mdl-29877393

ABSTRACT

A scanning laser-based back light three-dimensional (3D) display capable of rendering full-resolution, low crosstalk, and vivid 3D depth perception has been developed by incorporating time-sequential multiplexing and eye-tracking technologies. This system includes three main subsystems: a scanning laser module, a relay transfer unit created by combining multiple transmissive-type electrically addressed ferroelectric liquid crystal spatial light modulators (FLC-SLMs), and a dual-directional transmission screen (DDTS) unit that can produce different angular magnification factors in both the tangential and sagittal planes. The light beam is directed by the DDTS after transmission through FLC-SLMs, and left and right eye viewing zones are produced sequentially in accordance with the locations of clear apertures in the FLC-SLM that are controlled based on data from the eye-tracking system. Owing to the persistence of human vision, 3D images are formed as a result of the high-speed scanning backlight and fast response characteristics of the FLC-SLM. A prototype of the proposed 3D display was designed and built, and experiments were carried out. The experimental results verify the feasibility of the proposed scheme, and full-resolution images with natural 3D perception are demonstrated by the prototype.

5.
Appl Opt ; 56(32): 9090-9097, 2017 Nov 10.
Article in English | MEDLINE | ID: mdl-29131196

ABSTRACT

An iterative optimization algorithm is introduced to address the surface iterative errors as well as source extension issues in a freeform illumination system for producing satisfactory illumination distribution. A unique two-parameter coordinate system is utilized to represent the emitted ray directions. Then, the direction vector for the incident rays, which propagate through several surfaces, is obtained using ray-tracing techniques. Based on the mapping between the incoming rays and a target grid, a freeform surface is generated as a good starting design. An iterative optimization strategy is further employed to alleviate the deterioration of illumination distribution on the target region, and the uniformity of the illumination system is evaluated during optimization. Very few variables are demanded, and more flexibility in the design of the freeform surface is offered. Successive iterations can be performed until the desired result is attained. An optical system is used as an example to demonstrate the validity of the proposed method, and numerical simulations are carried out to evaluate the optical performance. The simulation results show that a small angular intensity distribution and prescribed rectangular illumination pattern can be achieved simultaneously.

6.
Appl Opt ; 56(19): 5450-5457, 2017 Jul 01.
Article in English | MEDLINE | ID: mdl-29047503

ABSTRACT

A subpixel area-based evaluation method for an improved slanted lenticular film that minimizes the crosstalk in a quasi-three-dimensional (Q3D) display is proposed in this paper. To identify an optimal slant angle of the film, a subpixel area-based measurement is derived to evaluate the crosstalk among viewing regions of the intended subpixel and adjacent unintended subpixel by taking the real subpixel shape and black matrix into consideration. The subpixel mapping, which corresponds to the optimal slant angle of the film, can then be determined. Meanwhile, the viewing zone characteristics are analyzed to balance the light intensity in both right and left eye channels. A compact and portable Q3D system has been built and appropriate experiments have been applied. The results indicate that significant improvements in both crosstalk and resolution can be obtained with the proposed technique.

7.
Appl Opt ; 55(28): 7847-7854, 2016 Oct 01.
Article in English | MEDLINE | ID: mdl-27828014

ABSTRACT

A time-sequential autostereoscopic three-dimensional (3D) display using a set of cylindrical optical elements (COEs) as the backlight steering is proposed. The operation principle of the system and its detailed design are described. In our system, the COEs control the direction of the backlight for the proposed system of the user's right and left views. Additionally, the displayed images can be observed under ambient lighting by implementing the high density light-emitting diode (LED) arrays. Compared to the first-generation array display, the image resolution is greatly improved by the addition of the time multiplexing technique. A prototype system using a set of COEs, LED arrays, two linear Fresnel lenses, and an elliptical diffuser is constructed. Here, the directional backlight beams are synchronized with the right and left images alternately displayed on the liquid crystal display (LCD) screen, and two convergent viewing zones are formed alternately in front of the user's eyes; then 3D images are perceived because of persistence of the vision of human eye. The experimental results show that the proposed method is a potential technology for 3D applications such as 3D television.

8.
Appl Opt ; 55(28): 7824-7829, 2016 Oct 01.
Article in English | MEDLINE | ID: mdl-27828016

ABSTRACT

A large aperture transmissive step-steering screen composed of a liquid crystal microprism array (LCMPA) deflector and a 90° twisted nematic liquid crystal (TN LC) polarization modulator is developed. The designed 3 in. (7.62 cm) device provides a steering angle of 0.95° that differs from the projected value by only 1.26% and the angular difference caused by dispersion is less than 5%. Using two-layer cascaded screens a three-direction beam steering system for stereoscopic displays is achieved with a steering step of 0.95°, undesired residual polarization contrast less than 2%, and high optical uniformity.

9.
Appl Opt ; 55(17): 4550-7, 2016 Jun 10.
Article in English | MEDLINE | ID: mdl-27409011

ABSTRACT

In this work, the off-axis imaging of a fan of rays with a rotationally symmetric mirror is studied, based on which a general construction method is proposed for the design of a rotationally symmetric ultrashort distance catadioptric projector. With the proposed method, the intermediate images at arbitrary planes of incidence can be obtained, and thus the designer has the freedom to choose suitable intermediate images to simplify the aberration correction of the catadioptric starting point. To prove the effectiveness of the proposed method, the construction process of a convex-type ultrashort distance catadioptric projector is presented. The intermediate image at the meridional plane is discontinuous, and the image distances for some fields are infinite. In contrast, the intermediate image at the sagittal plane is continuous, smooth, and finite-and thus is selected to correct the skew aberrations in the catadioptric starting point. An initial configuration, which has small aberrations, is obtained without increasing the system complexity. Further automatic optimization is applied to the initial configuration to get the optimal solution. The simulated performance of the optimal solution is excellent.

10.
Appl Opt ; 53(22): E69-76, 2014 Aug 01.
Article in English | MEDLINE | ID: mdl-25090357

ABSTRACT

This paper presents a field curvature correction method of designing an ultrashort throw ratio (TR) projection lens for an imaging system. The projection lens is composed of several refractive optical elements and an odd polynomial mirror surface. A curved image is formed in a direction away from the odd polynomial mirror surface by the refractive optical elements from the image formed on the digital micromirror device (DMD) panel, and the curved image formed is its virtual image. Then the odd polynomial mirror surface enlarges the curved image and a plane image is formed on the screen. Based on the relationship between the chief ray from the exit pupil of each field of view (FOV) and the corresponding predescribed position on the screen, the initial profile of the freeform mirror surface is calculated by using segments of the hyperbolic according to the laws of reflection. For further optimization, the value of the high-order odd polynomial surface is used to express the freeform mirror surface through a least-squares fitting method. As an example, an ultrashort TR projection lens that realizes projection onto a large 50 in. screen at a distance of only 510 mm is presented. The optical performance for the designed projection lens is analyzed by ray tracing method. Results show that an ultrashort TR projection lens modulation transfer function of over 60% at 0.5 cycles/mm for all optimization fields is achievable with f-number of 2.0, 126° full FOV, <1% distortion, and 0.46 TR. Moreover, in comparing the proposed projection lens' optical specifications to that of traditional projection lenses, aspheric mirror projection lenses, and conventional short TR projection lenses, results indicate that this projection lens has the advantages of ultrashort TR, low f-number, wide full FOV, and small distortion.

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