A low-cost low-maintenance ultraviolet lithography light source based on light-emitting diodes

Lab on a Chip ◽  
2015 ◽  
Vol 15 (1) ◽  
pp. 57-61 ◽  
Author(s):  
M. Erickstad ◽  
E. Gutierrez ◽  
A. Groisman
Keyword(s):  
Light Source ◽  
Light Emitting Diodes ◽  
Uv Light ◽  
Low Cost ◽  
Uniform Illumination ◽  
Large Area ◽  
Ultraviolet Lithography ◽  
Light Emitting

An LED-based UV-light source producing collimated uniform illumination over a large area is built and used to fabricate PDMS microchannels with near-rectangular profiles and depths up to 300 μm.

scholarly journals Colour-Encoded Electroluminescent White Light-emitting Diode Enabled by Perovskite-Cu-In-S Quantum Composites

2021 ◽  
Author(s):  
Seung-Bum Cho ◽  
Jung Inn Sohn ◽  
Sang-Seok Lee ◽  
Seung-Gyun Moon ◽  
Bo Hou ◽  
...  
Keyword(s):  
Quantum Dot ◽  
Light Source ◽  
White Light ◽  
Light Emitting Diodes ◽  
Light Emitting Diode ◽  
Large Area ◽  
Solution Processed ◽  
Light Emitting ◽  
Ambient Lighting ◽  
White Light Emitting Diodes

Solution-processed quantum dot (QD) white light-emitting diodes (WLEDs) have received much attention as a viable light source in the next-generation large-area ambient lighting, flexible photonics and full-colour display backlighting technologies....

scholarly journals Low-cost photolithography system for cell biology labs

2021 ◽  
Vol 7 (2) ◽  
pp. 550-553
Author(s):  
Benjamin K. Naggay ◽  
Kerstin Frey ◽  
Markus Schneider ◽  
Kiriaki Athanasopulu ◽  
Günter Lorenz ◽  
...  
Keyword(s):  
Light Source ◽  
Cell Biology ◽  
Soft Lithography ◽  
Uv Light ◽  
Low Cost ◽  
Cost Effective ◽  
Working Environment ◽  
Light Emitting ◽  
Set Up ◽  
High Level

Abstract Soft lithography, a tool widely applied in biology and life sciences with numerous applications, uses the soft molding of photolithography-generated master structures by polymers. The central part of a photolithography set-up is a mask-aligner mostly based on a high-pressure mercury lamp as an ultraviolet (UV) light source. This type of light source requires a high level of maintenance and shows a decreasing intensity over its lifetime, influencing the lithography outcome. In this paper, we present a low-cost, bench-top photolithography tool based on ninety-eight 375 nm light-emitting diodes (LEDs). With approx. 10 W, our presented lithography set-up requires only a fraction of the energy of a conventional lamp, the LEDs have a guaranteed lifetime of 1000 h, which becomes noticeable by at least 2.5 to 15 times more exposure cycles compared to a standard light source and with costs less than 850 C it is very affordable. Such a set-up is not only attractive to small academic and industrial fabrication facilities who want to enable work with the technology of photolithography and cannot afford a conventional set-up, but also microfluidic teaching laboratories and microfluidic research and development laboratories, in general, could benefit from this cost-effective alternative. With our self-built photolithography system, we were able to produce structures from 6 μm to 50 μm in height and 10 μm to 200 μm in width. As an optional feature, we present a scaled-down laminar flow hood to enable a dust-free working environment for the photolithography process.

Characterization of Polymer Light Emitting Diodes Fabricated by Ionically Self-Assembled Monolayer Technique

1999 ◽  
Vol 598 ◽  
Author(s):  
D. Marciu ◽  
M. B. Miller ◽  
J. R. Heflin ◽  
M. A. Murray ◽  
A. L. Ritter ◽  
...  
Keyword(s):  
Film Thickness ◽  
Indium Tin Oxide ◽  
Light Emitting Diodes ◽  
Low Cost ◽  
Electrolyte Solutions ◽  
Aluminum Electrode ◽  
Large Area ◽  
Self Assembled Monolayer ◽  
Light Emitting ◽  
Self Assembled

ABSTRACTIonically self-assembled monolayer (ISAM) films are a recently developed class of materials that allows detailed structural and thickness control at the sub-nanometer level combined with ease of manufacturing and low cost. The ISAM fabrication method simply involves the dipping of a charged substrate alternately into polycationic and polyanionic aqueous solutions at room temperatures. Importantly, the ISAM technique yields exceptionally homogeneous, large area films with excellent control of total film thickness. We describe detailed studies of ISAM light emitting diodes incorporating poly(para-phenylene vinylene) (PPV) as the light emitting polymer. The individual thickness of each monolayer and the interpenetration of adjacent layers can be precisely controlled through the parameters of the electrolyte solutions. The effects of the pH and ionic strength of the immersion solutions, the total film thickness, and the PPV thermal conversion parameters on the photoluminescence and electroluminescence yields have been systematically studied. The ISAM process also allows the advantage of depositing well-defined thicknesses of separate polymers at the indium tin oxide and the aluminum electrode interfaces.

scholarly journals Large-area and efficient perovskite light-emitting diodes via low-temperature blade-coating

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Shenglong Chu ◽  
Wenjing Chen ◽  
Zhibin Fang ◽  
Xun Xiao ◽  
Yan Liu ◽  
...  
Keyword(s):  
Low Temperature ◽  
Light Emitting Diodes ◽  
Low Cost ◽  
Sol Gel ◽  
Large Area ◽  
Lead Iodide ◽  
Light Emitting ◽  
Production Techniques ◽  
Methylammonium Lead Iodide ◽  
Blade Coating

AbstractLarge-area light-emitting diodes (LEDs) fabricated by mass-production techniques are needed for low-cost flat-panel lighting. Nevertheless, it is still challenging to fabricate efficient large-area LEDs using organic small molecules (OLEDs), quantum dots (QLEDs), polymers (PLEDs), and recently-developed hybrid perovskites (PeLEDs) due to difficulties controlling film uniformity. To that end, we report sol-gel engineering of low-temperature blade-coated methylammonium lead iodide (MAPbI3) perovskite films. The precipitation, gelation, aging, and phase transformation stages are dramatically shortened by using a diluted, organoammonium-excessed precursor, resulting in ultra-flat large-area films (54 cm2) with roughness reaching 1 nm. The external quantum efficiency of doctor-bladed PeLEDs reaches 16.1%, higher than that of best-performing blade-coated OLEDs, QLEDs, and PLEDs. Furthermore, benefitting from the throughput of the blade-coating process and cheap materials, the expected cost of the emissive layer is projected to be as low as 0.02 cents per cm2, emphasizing its application potential.

scholarly journals Converting a Common Low-Cost Document Scanner into a Multispectral Scanner

Sensors ◽  
2019 ◽  
Vol 19 (14) ◽  
pp. 3199
Author(s):  
Zohaib Khan ◽  
Faisal Shafait ◽  
Ajmal Mian
Keyword(s):  
Light Source ◽  
Multispectral Imaging ◽  
Light Emitting Diodes ◽  
Light Guide ◽  
Narrow Band ◽  
Low Cost ◽  
Multispectral Images ◽  
Light Emitting ◽  
Questioned Documents ◽  
Bank Notes

Forged documents and counterfeit currency can be better detected with multispectral imaging in multiple color channels instead of the usual red, green and blue. However, multispectral cameras/scanners are expensive. We propose the construction of a low cost scanner designed to capture multispectral images of documents. A standard sheet-feed scanner was modified by disconnecting its internal light source and connecting an external multispectral light source comprising of narrow band light emitting diodes (LED). A document was scanned by illuminating the scanner light guide successively with different LEDs and capturing a scan of the document. The system costs less than a hundred dollars and is portable. It can potentially be used for applications in verification of questioned documents, checks, receipts and bank notes.

A Multifunctional Molecular Modifier Enabling Efficient Large-Area Perovskite Light-Emitting Diodes

2020 ◽  
Author(s):  
Haoran Wang ◽  
Xiwen Gong ◽  
Dewei Zhao ◽  
Yong-Biao Zhao ◽  
Sheng Wang ◽  
...  
Keyword(s):  
Light Emitting Diodes ◽  
Large Area ◽  
Light Emitting

Performance of vertical type deep UV light-emitting diodes depending on the Ga-face n-contact hole density

2021 ◽  
Vol 118 (23) ◽  
pp. 231102
Author(s):  
Youn Joon Sung ◽  
Dong-Woo Kim ◽  
Geun Young Yeom ◽  
Kyu Sang Kim
Keyword(s):  
Light Emitting Diodes ◽  
Uv Light ◽  
Hole Density ◽  
Light Emitting ◽  
Deep Uv

Light source with light emitting diodes. Determination of limited frequencies and of the crest factor of illuminance meters and luminance meters

1989 ◽  
Vol 20 (5) ◽  
pp. 205-217
Author(s):  
J Deforges ◽  
P Garcia ◽  
J Bastie ◽  
F Marandet ◽  
J Bernard ◽  
...  
Keyword(s):  
Light Source ◽  
Light Emitting Diodes ◽  
Crest Factor ◽  
Light Emitting
Sign in / Sign up

Export Citation Format

Share Document