Maskless lithography laser source target light dose reversed mapping

2020 ◽  
Author(s):  
Shau-Yin Tseng ◽  
Jian-Wei Chen
Keyword(s):  
Light Dose ◽  
Laser Source ◽  
Maskless Lithography ◽  
Target Light

scholarly journals In vitro toxicity testing of phthalocyanines on different cell lines using a continuous laser source

2010 ◽  
Author(s):  
◽  
Kaminee Maduray
Keyword(s):  
Photodynamic Therapy ◽  
Cell Viability ◽  
Cancer Cells ◽  
Normal Skin ◽  
Light Dose ◽  
Laser Source ◽  
Normal Fibroblast ◽  
Melanoma Cancer ◽  
Skin Cells

Photodynamic therapy is a promising treatment for cancer. It involves the combination of a photosensitizer and light of an appropriate wavelength (laser source) to cause the destruction of cancer cells. Phthalocynanines are second–generation photosensitizers with enhanced photophysical and photochemical properties. In this in vitro study the effect of aluminium (AlTSPc) or zinc (ZnTSPc) tetrasulfophthalocyanines in its inactive and active state (laser induced) on melanoma (skin cancer cells), fibroblast (healthy normal skin cells) and keratinocyte (healthy normal skin cells) cells was evaluated. For each of the cell lines approximately 3 x 104 cells/ml were seeded onto 24-well cell culture plates and allowed to attach overnight, after which cells were treated with different concentrations of AlTSPc or ZnTSPc. The photosensitizers were synthesized at Rhodes University. After 2 hrs, cells were irradiated with a diode laser at a wavelength of 672 nm and a beam diameter of 1 cm. The laser power varied between 20-30 mW and the irradiation time was calculated to deliver a light dose of 4.5 J/cm2. Post-irradiated cells were incubated for 24 hrs before cell viability was measured using the CellTiter-BlueTM Viability Assay. Also, the efficacy of the light dose and laser source used for the killing of approximately 50% of the melanoma cancer cells were investigated. AlTSPc and ZnTSPc decreased cell viability of melanoma cancer cells to approximately 50% with photosensitizer concentrations of 40 μg/ml and 50 μg/ml respectively. These photosensitizer concentrations caused a slight decrease in the percentage cell viability of fibroblast and keratinocyte cells. Results for the dark toxicity assay showed that iii both photosensitizers in the presence of high concentrations (60 μg/ml – 100 μg/ml) showed cytotoxicity effects on melanoma cancer cells in their inactive state. This was not observed in fibroblast and keratinocyte cells treated under the same experimental conditions. The optimal AlTSPc and ZnTSPc concentrations in combination with the light dose of 4.5 J/cm2 was the most efficient in killing the melanoma cancer cells with reduced killing effects on healthy normal fibroblast and keratinocyte cells when compared to other light doses (2.5 J/cm2, 7.5 J/cm2 and 10 J/cm2). The irradiation of cells photosensitized with the optimal photosensitizer concentrations with a femtosecond laser using similar laser parameters to continuous wave laser experiments resulted in a reduction in the cell viability of healthy normal fibroblast and keratinocyte cells compared to melanoma cancer cells. The presence of DNA degradation on agarose gel, morphological changes like blebbing and ultrastructural changes like nucleus condensation indicated that photodynamic therapy treated melanoma cancer cells with the optimal concentrations of AlTSPc and ZnTSPc induced cell death via apoptosis. This concludes that low concentrations of AlTSPc and ZnTSPc activated with an appropriate laser source can be used to induce cell death in melanoma cancer cells. Both AlTSPc and ZnTSPc exhibit the potential to be used as a photosensitizer in photodynamic therapy for the treatment of melanoma cancer with the occurrence of minimal damage to surrounding healthy tissue.

LASER SOURCE OF POLARIZED PROTONS

1985 ◽  
Vol 46 (C2) ◽  
pp. C2-699-C2-701
Author(s):  
A. N. Zelenskii ◽  
S. A. Kokhanovskii ◽  
V. M. Lobashev ◽  
V. G. Polushkin
Keyword(s):  
Laser Source ◽  
Polarized Protons

10 THz Laser Source of Radiation

2002 ◽  
Vol 58 (5-6) ◽  
pp. 3
Author(s):  
Yu. Ye. Kamenev ◽  
V. K. Kiseliov ◽  
A. A. Filimonova
Keyword(s):  
Laser Source

Mercury vapor filter technology and ultraviolet laser source for flowfield imaging

1997 ◽  
Author(s):  
N. Finkelstein ◽  
W. Lempert ◽  
R. Miles ◽  
N. Finkelstein ◽  
W. Lempert ◽  
...  
Keyword(s):  
Mercury Vapor ◽  
Laser Source ◽  
Ultraviolet Laser

Wrinkling Poly(trimethylene 2,5-Furanoate) Free-standing Films: Nanostructure Formation and Physical Properties

2020 ◽  
Author(s):  
Michelina Soccio ◽  
Nadia Lotti ◽  
Andrea Munari ◽  
Esther Rebollar ◽  
Daniel E Martínez-Tong
Keyword(s):  
Irradiation Time ◽  
Polymer Surface ◽  
Laser Source ◽  
Free Standing ◽  
Force Microscopy ◽  
Nanostructure Formation ◽  
Physicochemical Changes ◽  
Angle Measurements ◽  
Atomic Force ◽  
Contact Angle Measurements

<p>Nanostructured wrinkles were developed on fully bio-based poly(trimethylene furanoate) (PTF) films by using the technique of Laser Induced Periodic Surface Structures (LIPSS). We investigated the effect of irradiation time on wrinkle formation using an UV pulsed laser source, at a fluence of 8 mJ/cm2. It was found that the pulse range between 600 and 4800 pulses allowed formation of periodic nanometric ripples. The nanostructured surface was studied using a combined macro- and nanoscale approach. We evaluated possible physicochemical changes taking place on the polymer surface after irradiation by infrared spectroscopy, contact angle measurements and atomic force microscopy. The macroscopic physicochemical properties of PTF showed almost no changes after nanostructure formation, differently from the results previously found for the terephthalic counterparts, as poly(ethyleneterephthalate), PET, and poly(trimethyleneterephthalate), PTT. The surface mechanical properties of the nanostructured PTF were found to be improved, as evidenced by nanomechanical force spectroscopy measurements. In particular, an increased Young’s modulus and higher stiffness for the nanostructured sample were measured. <br></p>

Innovative Technologies for Maskless Lithography and Non-Conventional Patterning

2008 ◽  
Author(s):  
Avideh Zakhor ◽  
Andrew Neureuther ◽  
R. F Pease ◽  
Olav Solgaard ◽  
Vivek Subramanian ◽  
...  
Keyword(s):  
Maskless Lithography ◽  
Innovative Technologies

Laser optoacoustic detection of trace concentration levels of ethylene, vinylchloride, and styrene in the atmosphere

1989 ◽  
Vol 54 (10) ◽  
pp. 2667-2673 ◽  
Author(s):  
Vojtěch Steiner ◽  
Pavel Engst ◽  
Zdeněk Zelinger ◽  
Milan Horák
Keyword(s):  
Detection Limit ◽  
Emission Line ◽  
Laser Line ◽  
Laser Source ◽  
Trace Concentration ◽  
Selective Determination ◽  
Hygienic Standard ◽  
Trace Concentrations ◽  
Concentration Levels

The optoacoustic analyzer with a tunable CO2 laser source employed in the present work permits a selective determination of ethylene in trace concentrations higher than 5 ppb (=detection limit for the 10P(14) emission line of the CO2 laser, ν = 949.5 cm-1) and of vinylchloride higher than 42 ppb (= detection limit for the 10P(22) CO2 laser line, ν= 942.4 cm-1). this method covers for both compounds the concentration range corresponding to the hygienic standard. It can be also used for the determination of styrene vapour with concentrations higher than 1.5 ppm.

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