Fabrication of SU-8 Microneedle Based on Backside Exposure Technology

2015 ◽  
Vol 645-646 ◽  
pp. 853-858 ◽  
Author(s):  
Li Qun Du ◽  
Zhong Zhou Wang ◽  
Xiao Peng Ruan ◽  
Sheng Li Chen ◽  
Qing Shan
Keyword(s):  
Light Intensity ◽  
Mass Production ◽  
Uv Light ◽  
Low Cost ◽  
Surface Profile ◽  
Optimization Method ◽  
Exposure Dose ◽  
Light Intensity Distribution ◽  
Microneedle Arrays ◽  
Simulation Results

An optimization method for fabricating 3D microneedle arrays with larger cone angles through backside exposure is demonstrated in this paper. A photo mask was designed to fabricate SU-8 microneedle based on diffraction of UV light. A circular hole diffraction was simulated with Matlab to obtain light intensity distribution. The simulation results show that the cone angles and surface profile can be adjusted by changing the thickness of substrate and exposure dose. Based on the simulation results, the microneedles with heights of 265 μm to 380 μm and cone angles in the range of 5.1° to 15.6° were fabricated by the backside exposure technology through one time UV lithography. Compared with previous approaches, the fabrication process in this paper takes advantages of simple, low cost and mass production.

Research of Micro-Stereolithography System with Dynamic Pattern Generator

2009 ◽  
Vol 16-19 ◽  
pp. 675-679 ◽  
Author(s):  
Guang Shen Xu ◽  
Xun Ming Ma ◽  
Huan Pan ◽  
Song Qiao Hu
Keyword(s):  
Light Intensity ◽  
Intensity Distribution ◽  
Laser Scanning ◽  
Uv Light ◽  
Low Cost ◽  
Pattern Generator ◽  
The Novel ◽  
Light Intensity Distribution ◽  
Dynamic Pattern ◽  
Imaging Plane

In order to fabricate micro/meso structures, a novel micro-stereolithography (SL) system with dynamic pattern generator using digital micro-mirror device (DMD) has been investigated. The micro-stereolithography system solidifies photo-sensitive resin with image mask generated by dynamic pattern generator. The micro-stereolithography system is made up of dynamic pattern generator, recoating system and control system. The dynamic pattern generator consists of parabolic concentrator, UV lamp, collimating lens, shutter, DMD and its control, lens and computer. UV light intensity distribution in the imaging plane is investigated. Uniformity UV light intensity distribution is obtained in the imaging plane with changing small area’s gray-scale, and the difference between maximum and minimum value of UV light intensity is 0.4µW/cm2. Small size parts with intricate microstructures have been fabricated with the novel SL system. Compared with laser scanning SL system, the advantage of the novel micro-SL system is that the new SL system can build small objects having micro-structures with low cost in shorter time. The novel micro-SL system provides a solution to the problem that has hampered the progress of SL process into high resolution with low cost.

Investigation of UV Light Intensity Distribution of Integral Micro-Stereolithography System

2010 ◽  
Vol 97-101 ◽  
pp. 3985-3988 ◽  
Author(s):  
Guang Shen Xu ◽  
Huan Pan ◽  
Xun Ming Ma ◽  
Sheng Luo ◽  
Rong Hua Qiu
Keyword(s):  
Light Intensity ◽  
Intensity Distribution ◽  
Least Squares Method ◽  
Uv Light ◽  
Experimental Investigations ◽  
Gray Scale ◽  
Light Intensity Distribution ◽  
Building Process ◽  
The Difference ◽  
Imaging Plane

The non-uniformity distribution of UV light intensity in the imaging plane of integral micro-Stereolithography (µSL) System will induces serious distortion of object in building process, and the building accuracy of the SL system can not be assured. To obtain uniformity distribution of UV light intensity, experimental investigations were performed to research the relationship of UV light intensity with position (x,y) in the imaging plane and gray-scale z of the pattern in the integral µSL System. Based on the experiment results, the model of UV light intensity was established with least squares method. According to the model, for a given point in the imaging plane of the µSL system, the UV light intensity can be changed with varying the gray-scale of the pattern. As a result, Uniformity UV light intensity distribution is obtained in the imaging plane, and the difference between maximum and minimum value of UV light intensity is 0.06µW/cm2. The uniformity UV light intensity distribution provides a foundation for building accurate microstructures with the µSL system.

scholarly journals Photoelectrical characteristics of UV organic thin-film transistor detectors

2017 ◽  
Vol 33 (2) ◽  
Author(s):  
Toan Thanh Dao
Keyword(s):  
Thin Film ◽  
Light Intensity ◽  
Gate Voltage ◽  
Gate Dielectric ◽  
Uv Light ◽  
Low Cost ◽  
Thin Film Transistor ◽  
Organic Thin Film ◽  
Organic Thin Film Transistor ◽  
Transistor Channel

In this paper, a pentacene photo organic thin-film transistor (photoOTFT) was fabricated and characterized. The gate dielectric acted as a sensing layer thanks to it strongly absorbs UV light. Electrical behaviors of photoOTFT were measured under 365 nm UV illumination from the gate electrode side. The current in transistor channel was significantly enhanced by photoelectrons at interface of buffer/gate dielectric. Photosensitivity increased with the light intensity but decreased with the applied gate voltage. Meanwhile the photoresponsivity decreased with the light intensity and increased with the applied gate voltage. The transistor responses well with the pulse of light with many cycles of light-on and light-off were tested. The best photosensitivity, photoresponsivity, rising time and falling time parameters of the device were found to be about 104, 0.12 A/W, and 0.2 s, respectively. The obtained photoelectrical results suggest that the photoOTFT can be a good candidate for practical uses in low-cost UV optoelectronics.

Study and design of dual stator permanent magnet machine with spoke-type configurations using phase-group concentrated-coil windings

2020 ◽  
Vol 64 (1-4) ◽  
pp. 1381-1389
Author(s):  
Dezhi Chen ◽  
Chengwu Diao ◽  
Zhiyu Feng ◽  
Shichong Zhang ◽  
Wenliang Zhao
Keyword(s):  
Permanent Magnet ◽  
Permanent Magnets ◽  
Low Cost ◽  
Dynamic Performance ◽  
Torque Ripple ◽  
Permanent Magnet Machine ◽  
Torque Density ◽  
Phase Group ◽  
High Torque ◽  
Simulation Results

In this paper, a novel dual-stator permanent magnet machine (DsPmSynM) with low cost and high torque density is designed. The winding part of the DsPmSynM adopts phase-group concentrated-coil windings, and the permanent magnets are arranged by spoke-type. Firstly, the winding structure reduces the amount of copper at the end of the winding. Secondly, the electromagnetic torque ripple of DsPmSynM is suppressed by reducing the cogging torque. Furthermore, the dynamic performance of DsPmSynM is studied. Finally, the experimental results are compared with the simulation results.

Visible Light Assisted Hantzsch Reaction: Synthesis of Polycyclic Dihydropyridines

2019 ◽  
Vol 16 (8) ◽  
pp. 676-682
Author(s):  
Ankusab Noorahmadsab Nadaf ◽  
Kalegowda Shivashankar
Keyword(s):  
Reaction Time ◽  
Light Intensity ◽  
Ammonium Acetate ◽  
Low Cost ◽  
Aromatic Aldehydes ◽  
Light Irradiation ◽  
High Yield ◽  
Short Reaction Time ◽  
Green Protocol ◽  
Dihydropyridine Derivatives

The polycyclic dihydropyridine nucleus represents the heterocyclic system of invaluable core motifs with wide applications in chemical, biological and physical properties. Although this kind of compounds have been extensively synthesized by other groups, the synthesis of these compounds under CFL light intensity were not explored. The synthesis of polycyclic dihydropyridine derivatives were achieved through the reaction of 4-hydroxycoumarin, aromatic aldehydes and ammonium acetate under CFL light irradiation conditions. A series of polycyclic dihydropyridine derivatives were prepared under CFL light irradiation conditions with high yield, short reaction time, ambient condition and without the use of catalyst. The results displayed an efficient method for the synthesis of polycyclic dihydropyridine derivatives. Clean profile, short reaction time, low cost and use of CFL light intensity instead of catalyst making it a genuinely green protocol.

scholarly journals Design of a Secondary Freeform Lens of UV LED Mosquito-Trapping Lamp for Enhancing Trapping Efficiency

Crystals ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 335 ◽  
Author(s):  
Wei-Hsiung Tseng ◽  
Diana Juan ◽  
Wei-Cheng Hsiao ◽  
Cheng-Han Chan ◽  
Hsin-Yi Ma ◽  
...  
Keyword(s):  
Light Intensity ◽  
Intensity Distribution ◽  
Light Emitting Diode ◽  
Trapping Efficiency ◽  
Axially Symmetric ◽  
Light Intensity Distribution ◽  
Light Emitting ◽  
Led Light ◽  
Uv Led ◽  
Freeform Lens

In this study, our proposed ultraviolet light-emitting diode (UV LED) mosquito-trapping lamp is designed to control diseases brought by insects such as mosquitoes. In order to enable the device to efficiently catch mosquitoes in a wider area, a secondary freeform lens (SFL) is designed for UV LED. The lens is mounted on a 3 W UV LED light bar as a mosquito-trapping lamp of the new UV LED light bar module to achieve axially symmetric light intensity distribution. The special SFL is used to enhance the trapping capabilities of the mosquito-trapping lamp. The results show that when the secondary freeform surface lens is applied to the experimental outdoor UV LED mosquito-trapping lamp, the trapping range can be expanded to 100π·m2 and the captured mosquitoes increased by about 300%.

Fast-resist image estimation methodology using light-intensity distribution

1995 ◽  
Author(s):  
Keisuke Tsudaka ◽  
Manabu Tomita ◽  
Minoru Sugawara ◽  
Hiroichi Kawahira ◽  
Satoru Nozawa
Keyword(s):  
Light Intensity ◽  
Intensity Distribution ◽  
Light Intensity Distribution ◽  
Image Estimation

scholarly journals Whispering Gallery Mode Based Optical Fiber Sensor for Measuring Concentration of Salt Solution

2013 ◽  
Vol 2013 ◽  
pp. 1-4 ◽  
Author(s):  
Chia-Chin Chiang ◽  
Jian-Cin Chao
Keyword(s):  
Optical Fiber ◽  
Mass Production ◽  
Low Cost ◽  
Optical Fiber Sensor ◽  
Whispering Gallery Mode ◽  
Solution Concentration ◽  
Fiber Sensor ◽  
Average Sensitivity ◽  
Whispering Gallery ◽  
The Right

An optical fiber solution-concentration sensor based on whispering gallery mode (WGM) is proposed in this paper. The WGM solution-concentration sensors were used to measure salt solutions, in which the concentrations ranged from 1% to 25% and the wavelength drifted from the left to the right. The experimental results showed an average sensitivity of approximately 0.372 nm/% and anR2linearity of 0.8835. The proposed WGM sensors are of low cost, feasible for mass production, and durable for solution-concentration sensing.

Sign in / Sign up

Export Citation Format

Share Document