Jau-Sheng Wang's research while affiliated with National Sun Yat-sen University and other places

... However, because of the short wavelength and high energy of deep-UV light, organic encapsulation materials undergo UV degradation under long-term deep-UV light radiation and exhibit low transmittance in the DUV region. This phenomenon seriously affects the light efficiency and reliability of DUV-LEDs [13][14][15]. Considering the aforementioned shortcomings of organic materials, in the mainstream design of DUV-LED packaging, a quartz glass lens is used as a cover layer to achieve hermetic packaging, such as three-dimensional (3D) glass packaging and 3D ceramic substrate packaging, to improve reliability [16][17][18]. However, because of the large differences in refractive indices, Fresnel reflection losses occur at the glass-air and chip-air interfaces. ...

... Due to the inherent superiority of compact size, light weight, corrosion resistance, remote operation capability and immunity to electro-magnetic interference (EMI), optical fiber-based devices have become an outstanding alternative for acoustic wave detection and have attracted great research interests, such as fiber interferometers [8][9][10][11][12][13][14][15][16][17][18], fiber gratings [19][20][21][22], specialty fibers [23,24], and fiber laser [25][26][27][28], etc. Among different optical acoustic sensor structures, diaphragm based Fabry-Pérot (FP) cavity is a significant candidate structure for acoustic wave or even infrasound sensing [11][12][13][14][15][16][17][18] due to its unique characteristics of reflection-based working principle, which allows it to be easily packaged as sensing probes. ...

... Therefore, it is common for cladding materials to have lower refractive indices and similar thermal expansion coefficients to that of the core. Effective cladding methods include the magnetron sputtering [12], Sol-Gel method [13,14], liquid phase epitaxy [15], co-drawing laser heating pedestal growth (LHPG) [16][17][18][19][20][21][22][23][24], ion implantation [25][26][27][28], and micro-structure cladding [7,29,30]. ...

... Laser welding of transparent materials, including glasses, has been developed in the past years (Richter et al., 2015;Miyamoto et al., 2011). Bonding glass by welding is applied in several industrial fields, such as optics, insulation for windows, microelectromechanical systems (MEMS), opto-electronic and medical devices (Shun-Yuan et al., 2012;Cao et al., 2013;Memon et al, 2019). Many methods have been developed to bond the two pieces of glass by laser welding. ...

... Aging of QD-WLEDs can lead to a series of negative effects, such as changes in CCT, degradation of the color-rendering performance, device heating, etc., which eventually results in a shortened working lifetime and reduced lighting performance. The performance degradation of QD-WLEDs is divided into spectral variations and heating, with the former leading to a decrease in lighting quality and the latter leading to a reduction in working lifetime [7,[16][17][18][19]. Obviously, the performance degradation of QD-WLEDs is related to different parameters. ...

... This approach helps laser processing and allows enhancing the structural characteristics of the single-crystal fiber produced. Similarly, in the last 10 years, cladded, single-crystalline fibers, mainly used as amplifiers, have been produced from bulk crystal seeds covered by Sol-Gel or embedded into silica or borosilicate hollow tubes, among other coating approaches [35][36][37][38][39]. Furthermore, some works from Rutgers University (Piscataway, NJ, USA) reported the growth from Pt wires together with the use of seed crystals or presintered ceramics as feed rods [40][41][42]. ...

... However, lower treatment temperatures and shorter treatment times are desired to prevent decomposition of the organic moiety in organosilicas 8,9 , to decrease energy use during calcination, or to allow for application of the layer on a supporting substrate with a limited thermal stability [10][11][12][13] . Researchers have investigated several strategies to limit the treatment temperature or duration for hybrid and inorganic systems: a long-term treatment at low temperatures 14 , flash heating at high temperatures [15][16][17][18][19] , or a treatment with acids that renders thermal treatment unnecessary 2 . ...

... Still, only the C band has been exploited due to the outstanding performance of erbium-doped fiber amplifiers (EDFAs) [5]. In this case, the bandwidth of optical amplifiers needs to be expanded to drive the development of future optical networks [6][7][8][9]. Integrated optical circuits are essential parts of optical networks [10,11], and waveguide amplifiers are specially developed to compensate for the losses generated in them [12][13][14][15][16]. Up to now, research on waveguide amplifiers has mainly focused on a single band, such as the C band or S band [17,18]. If the gain bandwidth can be expanded to multi-band, the working efficiency of WDM will be significantly improved. ...

... However, phosphors have some disadvantages in packaging. For example, organic polymer used as a packaging material has poor heat dispersion so that it often brings about the problems of discolor and aging leading to the devices failure [20]. In addition, the refractive indexes between phosphors and encapsulation resin are different, which will cause light scattering and degenerate the luminous efficiency [21,22]. ...

... Pecht and Nash [66], in their case study conducted on light-emitting diode (LED) lasers, observed that the devices exhibited a gradually occurring wear-out failure mechanism. Similarly, Wang et al. [67] evaluated LED packages and found only wear-out failures for packages with various encapsulation materials. Mattila et al. [68], in their study on the reliability of electronic component boards, observed only wear-out failures at all testing temperatures. ...