Recent progress in negative-working photosensitive and thermally stable polymers

The trend in the development and manufacturing of Complementary Metal Oxide Semiconductor (CMOS) image sensors is to miniaturize pixels on the chips and hence to improve their imaging characteristics by providing a higher image resolution. As CMOS technology scales down into submicron regions, the conventional color filters are no longer suitable for generating the desired optical density. The major drawback of the conventional color filters produced from pigment-based positive tone photosensitive compositions, is the heterogeneous dispersion of pigments in photoresist composition resulting in color irregularities due to coarse particles of the pigments. One of the most perspective ways to solve this problem is a replacing the pigment with a dye as a coloring agent and thus, increasing solubility of the latter to obtain a homogeneous colored photoresist composition. In this paper, several novel red dye-containing materials are synthesized and tested to provide a redcolored photosensitive composition. This red-colored photosensitive composition is very promising for application as color filters for CMOS image sensors with high resolution and high level of integration architecture.

The behavior of random telegraph signal (RTS) noise in metal oxide semiconductor field effect transistor (MOSFETs) with different oxidation processes and its effects on the readout circuit in complementary MOS (CMOS) image sensor were experimentally studied. Statistically, RTS noise in large number of devices have been measured both in the device with single oxide and dual oxide and we analyzed its amplitude and power spectrum density. Through the analysis, we found that there are significantly different behaviors of RTS noise between single oxide devices and dual oxide devices due to different characteristic of oxide traps. We not only provided information of traps in both single and dual oxide devices but also applied different RTS noise behavior of both two cases to readout circuits in CMOS image sensor.

Japan Broadcasting Corp. (NHK) has been researching and developing Super Hi-Vision with 33 megapixels (7680 pixels by 4320 lines of resolution) as the next-generation ultra-high-definition television (UHDTV) broadcast system. In 2011, NHK reported that it had decided to double the frame rate of Super Hi-Vision video to 120 Hz to improve its motion portrayal quality. This UHDTV system has been standardized as the International Telecommunications Union Recommendations Section's Recommendation BT.2020. This paper reports on 120 Hz Super Hi-Vision devices that have been developed. One is a 120 Hz Super Hi-Vision image-capture device that uses three 120 Hz, 33-megapixel complementary metal oxide semiconductor image sensors. The sensors use 12-bit analog-to-digital converters and operate at a data rate of 51.2 Gbits/sec. A 120 Hz Super Hi-Vision projector has also been developed using three 8-megapixel liquid crystal on silicon chips. These 120 Hz Super Hi-Vision devices were exhibited at NHK's open house in May 2012 and demonstrated superb picture quality with less motion blur.

A 20-MHz switching high-speed light-modulating device for three-dimensional (3-D) image capturing and its system prototype are presented. For 3-D image capturing, the system utilizes a time-of-flight (TOF) principle by means of a 20-MHz high-speed micromachined electro-absorptive modulator, the so-called optical shutter. The high-speed modulation is obtained by utilizing the electro-absorption mechanism of the multilayer structure, which has an optical resonance cavity and light-absorption epilayers grown by metal organic chemical vapor deposition process. The optical shutter device is specially designed to have small resistor–capacitor–time constant to get the high-speed modulation. The optical shutter is positioned in front of a standard high-resolution complementary metal oxide semiconductor image sensor. The optical shutter modulates the incoming infrared image to acquire the depth image. The suggested novel optical shutter device enables capturing of a full high resolution-depth image, which has been limited to video graphics array (VGA) by previous depth-capturing technologies. The suggested 3-D image sensing device can have a crucial impact on 3-D–related business such as 3-D cameras, gesture recognition, user interfaces, and 3-D displays. This paper presents micro-opto-electro-mechanical systems-based optical shutter design, fabrication, characterization, 3-D camera system prototype, and image evaluation.

We demonstrate a silo-filter (SF) complementary metal-oxide semiconductor (CMOS) image sensor for a chip-scale fluorescence microscope. The extruded pixel design with metal walls between neighboring pixels guides fluorescence emission through the thick absorptive filter to the photodiode of a pixel. Our prototype device achieves 13 μm resolution over a wide field of view (4.8 mm × 4.4 mm). We demonstrate bright-field and fluorescence longitudinal imaging of living cells in a compact, low-cost configuration.

A 4 x 4 pixel array with analog on-chip processing has been fabricated within a 0.35 mum complementary metal oxide semiconductor process as a prototype sensor for laser Doppler blood flow imaging. At each pixel the bandpass and frequency weighted filters necessary for processing laser Doppler blood flow signals have been designed and fabricated. Because of the space constraints of implementing an accurate omega(0.5) filter at the pixel level, this has been approximated using the "roll off" of a high-pass filter with a cutoff frequency set at 10 kHz. The sensor has been characterized using a modulated laser source. Fixed pattern noise is present that is demonstrated to be repeatable across the array and can be calibrated. Preliminary blood flow results on a finger before and after occlusion demonstrate that the sensor array provides the potential for a system that can be scaled to a larger number of pixels for blood flow imaging.

Radon (Rn-222) is the main source of radiation exposure to human beings from natural radiation; it is of great significance to study the measuring methods and measuring instruments of radon for natural radiation protection. In recent years, the application of pixel detectors in radiation detection has attracted attention. In this paper, a Commercial Off-the-Shelf Complementary Metal Oxide Semiconductor (COTS CMOS) image sensor which replaces the glass for protection covering in front of the sensors was used to perform a series of measurements to identify alpha particles. During the experiment, the CMOS image sensor was used to record a video during the sampling period, and then use the FFmpeg software to take screenshots of the video by frame. MATLAB was used to count bright spots from the image frames. A measurement chamber was designed to measure radon concentrations, and when the relative humidity was constant, the count of alpha particles by the CMOS image sensor increased along with the increase of the concentration. The experiments verified the feasibility of the low-cost COTS CMOS image sensors to monitor radon.

Star sensor is an essential component of spacecraft attitude control system. Spatial radiation can cause star sensor performance degradation, abnormal work, attitude measurement accuracy and reliability reduction. Many studies have already been dedicated to the radiation effect on Charge-Coupled Device (CCD) and Complementary Metal Oxide Semiconductor (CMOS) image sensors, but fewer studies focus on the radiation effect of star sensor. The innovation of this paper is to study the radiation effects from the device level to the system level. The influence of the degradation of CCD and CMOS image sensor radiation sensitive parameters on the performance parameters of star sensor is studied in this paper. The correlation among the radiation effect of proton, the non-uniformity noise of CCD and CMOS image sensor and the performance parameter of star sensor is analyzed. This paper establishes a foundation for the study of error prediction and correction technology of star sensor on-orbit attitude measurement, and provides some theoretical basis for the design of high performance star sensor.

Image sensors are the core components of computer, communication, and consumer electronic products. Complementary metal oxide semiconductor (CMOS) image sensors have become the mainstay of image-sensing developments, but are prone to leakage current. In this study, we simulate the CMOS image sensor (CIS) film stacking process by finite element analysis. To elucidate the relationship between the leakage current and stack architecture, we compare the simulated and measured leakage currents in the elements. Based on the analysis results, we further improve the performance by optimizing the architecture of the film stacks or changing the thin-film material. The material parameters are then corrected to improve the accuracy of the simulation results. The simulated and experimental results confirm a positive correlation between measured leakage current and stress. This trend is attributed to the structural defects induced by high stress, which generate leakage. Using this relationship, we can change the structure of the thin-film stack to reduce the leakage current and thereby improve the component life and reliability of the CIS components.

Visible Light Positioning (VLP) is widely recognized as a cost-effective solution for indoor positioning with increasing demand. However, the nonlinearity and highly complex relationship between three-dimensional world coordinate and two-dimensional image coordinate hinders the good performance of image-sensor-based VLP. Therefore, there is a need to develop effective VLP algorithms to locate the positioning terminal using image sensor. Besides, due to the high computational cost of image processing, most existing VLP systems do not achieve satisfactory performance in terms of real-time ability and positioning accuracy, both of which are significant for the performance of indoor positioning system. In addition, the accurate identification of the ID information of each LED (LED-ID) is important for positioning, because if the LED-ID is not recognized well, the positioning can only be achieved in a particular positioning unit and cannot be applied to a large scene with many LEDs. Therefore, an effective image-sensor-based double-light positioning system is proposed in this paper to solve the above problems. We also set up relevant experiments to test the performance of the proposed system, which utilizes the rolling shutter mechanism of the Complementary Metal Oxide Semiconductor (CMOS) image sensor. Machine learning was used to identify the LED-ID for better results. Simulation results show that the proposed double-light positioning system could deliver satisfactory performance in terms of both the real-time ability and the accuracy of positioning. Moreover, the proposed double-light positioning algorithm has low complexity and takes the symmetry problem of angle into consideration, which has never been considered before. Experiments confirmed that the proposed double-light positioning system can provide an accuracy of 3.85 cm with an average computing time of 56.28 ms, making it a promising candidate for future indoor positioning applications.

In this study, we used a Complementary Metal Oxide Semiconductor (CMOS) image sensor with immobilizing antibodies on its surface to detect human cytokines, which are activators that mediate intercellular communication including expression and control of immune responses. The CMOS image sensor has many advantages over the Charge Couple Device, including lower power consumption, operation voltage, and cost. The photodiode, a unit pixel component in the CMOS image sensor, receives light from the detection area and generates digital image data. About a million pixels are embedded, and size of each pixel is 3 x 3 μm. The chemiluminescence reaction produces light from the chemical reaction of luminol and hydrogen peroxide. To detect cytokines, antibodies were immobilized on the surface of the CMOS image sensor, and a sandwich immunoassay using an HRP-labeled antibody was performed. An HRP-catalyzed chemiluminescence reaction was measured by each pixel of the CMOS image sensor. Pixels with stronger signals indicated higher cytokine concentrations; thus, we were able to measure human interleukin-5 (IL-5) at femtomolar concentrations.

This paper focuses on the development of Complementary metal-oxide semiconductor (CMOS) image sensor and its applications in aerospace, medical and automotive fields. Firstly, the representative events in history and the contributions of some companies to CMOS image sensor are described. Subsequently, some characteristics of CMOS image sensor are analyzed in the image field involved. In order to evaluate the performance of CMOS image sensor, single even effect and electronic endoscope structures are analyzed and active and passive range finder experiments are carried out. The results show that the imaging based on CMOS sensor can fully meet the requirements of imaging applications in many fields.

In this study, we propose a new complementary metal-oxide semiconductor (CMOS) image sensor to extend the dynamic range. The proposed active pixel sensor (APS) uses a gate/body-tied PMOSFET-type (GBT) photodetector and an output voltage feedback structure. Although the size of the proposed APS is slightly larger than a conventional APS, the dynamic range of the proposed pixel is much wider than a conventional APS. And the proposed APS has a varied dynamic range from adjusting the reference voltage. The proposed APS has been designed and fabricated by using 0.35 μm 2-poly 4-metal standard CMOS technology, and its characteristics have been evaluated.

The reaction between a carbonyl group (aldehyde or ketone) with amine in suitable condition, the Schiff base compounds with an amine group with the general structure R1R2C=NR3 (R3 ≠ H) was prepared [1, 2]. These compounds were first prepared by German scientist Hugo Schiff. The Schiff base compounds are widely used as a ligand in the coordination chemistry [3, 4]. The division of these compounds is diverse and depending on the various parameters, they are divided into symmetric, asymmetrical, anionic, neutral types and etc. But in most cases the division of these compounds is based on the number of atoms that are coordinated to the center ion. Accordingly, they are divided into mono-, bi- and multi-dentate ligands. Important groups of these compounds are chelated bi-and tetra-dentate ligands, which can be obtained from the reaction of salicylic aldehyde and amine derivatives [5, 6]. The simplicity of providing, having different colors, stabilizing metal complexes and diverse applications has led many research groups to work on these compounds [1, 2, 5, 6]. The most important properties of these compounds are anion sensor [6–8] and avoid steel corrosion [9, 10]. In recent years the innovation of novel Schiff base polymers as thermally stable polymers play a vital role in many areas, among that the most important factor of thermally stable polymers for different industry. Because of that, these advances are interested in improvement of heat and thermal stability and safety. Day to day in this globalization, thermal stable polymers requires a long shelf life, along with monitoring the safety and quality based upon international standards. In this chapter it inculcates, thermally stable polymers such as PA, PI and PES and its stability, long life, mechanical and thermal properties for different applications.

The charge-coupled device (CCD) has been developed primarily as a compact image sensor for consumer and industrial markets, but is now also the preeminent visible and ultraviolet wavelength image sensor in many fields of scientific research including space-science and both Earth and planetary remote sensing. Today’s scientific or science-grade CCD will typically maximise pixel count, focal plane coverage, photon detection efficiency over the broadest spectral range and signal dynamic range whilst maintaining the lowest possible readout noise. The relatively recent re-emergence of complementary metal oxide semiconductor (CMOS) image sensor technology is arguably the most important development in solid-state imaging since the invention of the CCD. Current sub-micron CMOS technology now enables the integration on a single silicon chip of a large array of photodiode pixels alongside all of the ancillary electronics needed to address the array and digitise the resulting analogue video signal. Compared to the CCD, CMOS promises a more compact, lower mass, lower power and potentially more radiation tolerant camera.