Grating Rhomb Diode Laser Power Combiner

1987 ◽  
Author(s):  
Peter O. Minott ◽  
James B. Abshire
Keyword(s):  
Diode Laser ◽  
Laser Power ◽  
Power Combiner

scholarly journals Immunity to Laser Power Variation in a DFB Diode Laser Based Optical Gas Sensor Using a Division Process

Sensors ◽  
2015 ◽  
Vol 15 (4) ◽  
pp. 9582-9591 ◽  
Author(s):  
Hengtai Chang ◽  
Jun Chang ◽  
Qingjie Huang ◽  
Qiang Wang ◽  
Changbin Tian ◽  
...  
Keyword(s):  
Gas Sensor ◽  
Diode Laser ◽  
Laser Power ◽  
Power Variation ◽  
Division Process ◽  
Optical Gas Sensor

Transscleral Red Laser Cyclophotocoagulation for the Treatment of Therapy-Resistant Inflammatory Glaucoma

2007 ◽  
Vol 17 (4) ◽  
pp. 550-556 ◽  
Author(s):  
P.M. Puska ◽  
A.H.A. Tarkkanen
Keyword(s):  
Intraocular Pressure ◽  
Retrospective Study ◽  
Diode Laser ◽  
Laser Power ◽  
Application Time ◽  
Chronic Uveitis ◽  
Phthisis Bulbi ◽  
The Mean

Purpose To evaluate in a retrospective study the long-term usefulness of red 647 nm krypton and 670 nm diode laser for transscleral contact cyclophotocoagulation (CPC) in the treatment of therapy-resistant inflammatory glaucoma. Methods The authors treated 48 eyes of 38 consecutive patients (mean age 36.8 years, range 6–81 years) with therapy-resistant inflammatory glaucoma secondary to chronic uveitis (45/48), chronic scleritis (1/48), or combined scleritis with keratouveitis (2/48) using transscleral red 647 nm Krypton or 670 nm Diode laser. All eyes had failed maximum tolerated medical therapy and 19/48 (40%) eyes also previous antiglaucoma surgery. Laser power at the scleral surface was 0.35 to 0.45 W and the application time 10 seconds each. The follow-up was 42.8± 40.0 (range 2–145) months. Results The mean preoperative intraocular pressure (IOP) of 35.6±8.1 mmHg fell to 6–21 mmHg level in 75% after one or repeated CPC. Among adult patients this was achieved in 85%, among children in 54%. More than one treatment was needed in 52%. No cases of hypotony, phthisis bulbi, or other devastating complications occurred. Conclusions Transscleral CPC using red 647 nm krypton or 670 nm diode laser is an effective and well-tolerated procedure for the treatment of therapy-resistant inflammatory glaucoma in adults. CPC can be considered before incisional antiglaucoma surgery with a shunt or antimetabolites is undertaken

Five-frame phase-shifting algorithm insensitive to diode laser power variation

2001 ◽  
Vol 197 (1-3) ◽  
pp. 37-42 ◽  
Author(s):  
M. Afifi ◽  
K. Nassim ◽  
S. Rachafi
Keyword(s):  
Diode Laser ◽  
Laser Power ◽  
Phase Shifting ◽  
Power Variation

Diode Laser Cure of Thermosetting Powders for Writing on Painted and Unpainted Metallic Surfaces

2009 ◽  
Author(s):  
Loredana Santo ◽  
Vincenzo Tagliaferri ◽  
Federica Trovalusci
Keyword(s):  
Diode Laser ◽  
Laser Power ◽  
Visual Inspection ◽  
Metallic Surfaces ◽  
Electrostatic Deposition ◽  
Automotive Components ◽  
Scan Speed ◽  
Innovative System ◽  
Fixed Path ◽  
Scratch Tests

This paper describes an innovative system to make writings or patterns on painted or unpainted metallic surfaces by diode laser cure of thermosetting powders. The process is very interesting to personalize objects such as automotive components and others. An electrostatic deposition of commercial thermosetting powder is performed on metallic surfaces, the laser beam passes on the deposited powder following a fixed path and cures it. A process map was found in terms of laser power and scan speed. The laser power is in the range 55–70 W for a scan speed of 1 or 2 mm/s in the case of metallic surfaces, while the power is in the range 35–50 W for the same scan speeds in the case of painted surfaces. Visual inspection and scratch tests were performed in order to evaluate the aspect and the adhesion to the substrate. Very good results were found demonstrating that the diode laser is a useful tool to make writing.

scholarly journals Tissue coagulation in laser hemorrhoidoplasty – an experimental study

Open Medicine ◽  
2020 ◽  
Vol 15 (1) ◽  
pp. 185-189 ◽  
Author(s):  
Donatas Danys ◽  
Julius Pacevicius ◽  
Gabija Makunaite ◽  
Rolandas Palubeckas ◽  
Antanas Mainelis ◽  
...  
Keyword(s):  
Diode Laser ◽  
Laser Power ◽  
Tissue Injury ◽  
Laser Exposure ◽  
Activation Time ◽  
Coagulation Defect ◽  
Significant Difference ◽  
Perianal Tissue ◽  
The Subject ◽  
A New Technique

AbstractBackgroundLaser hemorrhoidoplasty (LHP) is a new technique for treatment of hemorrhoids. The exact extent of coagulation is not visible at the time of the procedure. There currently is no experimental or clinical data on the subject.ObjectiveTo evaluate the length of coagulation defect according to power and activation time of 1470nm diode laser on the perianal tissue model.MethodsFresh anorectal tissue of twenty-four pigs was used to produce 54 experimental samples. Each sample was randomly assigned to the laser power of 6, 8 and 10 W and 1, 2 or 3-second pulses. The procedure was performed using Biolitec Ceralas © diode laser with 1.85 mm optical fiber. The fiber was inserted in a manner, similar to intrahemorrhoidal laser application. Samples were evaluated using low-power and high-power light microscopy by a single pathologist. The length of tissue injury was measured on high-magnification microscopy.ResultsThe longest tissue injury (mean 3.93 mm) was caused by the longest laser exposure time (3 sec) with no significant difference between laser power used.Conclusions8 W 3-second application of the 1470nm diode laser results in coagulation area approximately 4 mm, and further coagulation should be initiated approximately 5 mm from the first one.

Investigation of the Characteristic of the Nd:YAG Laser for Standard Wavelength in Metrology

2013 ◽  
Vol 770 ◽  
pp. 398-401
Author(s):  
Prayut Potirak ◽  
Monludee Ranusawud ◽  
Pichet Limsuwan ◽  
Prathan Buranasiri
Keyword(s):  
Second Harmonic Generation ◽  
Diode Laser ◽  
Harmonic Generation ◽  
Nd:Yag Laser ◽  
Laser Power ◽  
Second Harmonic ◽  
Harmonic Generator ◽  
Second Harmonic Generator ◽  
532 Nm ◽  
Nd:Yag Crystal

This research studied characteristics of the Nd:YAG laser with second harmonic generation (SHG) at 532 nm. It can be develop as a standard wavelength according to the recommendation made by the Comite International des Poids et Measures (CIPM). This study investigates various parameters that effect wavelength and laser power of the Nd:YAG laser such as injection current of diode laser, temperature of Nd:YAG crystal and second harmonic generator crystal. Its wavelength can be tuned in the range of standard wavelength at 532.24503 nm with 10-7 of stability.

Traceable laser power measurements of diode laser radiation in the near infrared

MAPAN ◽  
2010 ◽  
Vol 25 (1) ◽  
pp. 29-35 ◽  
Author(s):  
Friedhelm Brandt ◽  
Stefan Kück ◽  
André Grütz
Keyword(s):  
Laser Radiation ◽  
Diode Laser ◽  
Laser Power ◽  
Near Infrared ◽  
Power Measurements

Cladding of Inconel 625+WC Composite Coatings Using a Direct Diode Laser

2014 ◽  
Vol 1036 ◽  
pp. 212-217
Author(s):  
Damian Janicki
Keyword(s):  
Diode Laser ◽  
Laser Power ◽  
Erosion Resistance ◽  
Volume Fraction ◽  
Composite Coatings ◽  
Optical Metallography ◽  
Inconel 625 ◽  
Homogeneous Distribution ◽  
Wear Properties ◽  
Low Degree

In the present study, a high power direct diode laser (HPDDL) was used to deposit composite coatings consisted of Ni-based superalloy Inconel 625 matrix and of WC reinforcement particles with a volume fraction of 60%. The influence of parameters, such as laser power beam (heat input) and WC particles size in the cladding powder on the coatings microstructure and erosion wear properties was investigated. The coatings were examined by optical metallography and scanning electron microscopy. The results showed that direct diode laser cladding provides non-porous coatings with homogeneous distribution of WC particles and very low degree of WC dissolution during cladding process. Erosion resistance of the composite coatings decreases with the size of WC particles decreasing.

scholarly journals Experimental justification of laser parameters for preventive laser (970 nm) vessel coagulation in intraoperative bleeding

2019 ◽  
Vol 17 (4) ◽  
pp. 57-61
Author(s):  
E. E. Kozyreva ◽  
M. A. Ryabova
Keyword(s):  
Diode Laser ◽  
Laser Power ◽  
Vascular Wall ◽  
Intraoperative Bleeding ◽  
Delayed Bleeding ◽  
Small Vessels ◽  
Vascular Bed ◽  
Duration Of Surgery ◽  
Experimental Justification ◽  
Surgical Field

Intraoperative bleeding impairs visualization of the surgical field. Working in a practically bloodless operating field reduces the duration of surgery and reduces the need for cautery use, which reduces pain in the postoperative period and the risk of delayed bleeding after tonsillectomy.Objective – to select the parameters of a diode laser with a wavelength of 970 nm in order to get optimal hemostatic effect and to develop a technique for safe preventive coagulation of vessels in the surgical wound using diode laser with a wavelength of 970 nm for their bloodless section.Materials and methods. 47 Wistar rats weighing 300–400 g were used in the experiment. After preparation of the surgical field, three groups of vessels were isolated from each rat. The rat vascular bed was used as a model of tonsillar vascular bed in the patients undergoing tonsillectomy. All animals were divided into groups, depending on the laser power. For the experiment we used a diode surgical laser with a wavelength of 970 nm in a constant mode, a fiber diameter of 400 microns. After coagulation of each vessel, a visual and microscopic assessment of the vessels was performed. The study of the possibility of vascular coagulation was evaluated after the vessel was cross-sectioned with a scalpel.Results. Damage to the walls of blood vessels was not observed at powers from 5.0 W to 7.0 W. At the same time, at the laser power from 5.0 W to 6.0 W there was no hemostasis after crossing the vessels. At a power of 6.5 W, adequate hemostasis was observed only in 42 % of cases. The coagulation mode of a diode laser with a wavelength of 970 nm, which is the most effective and safe for surrounding tissues, was observed at a power of 7.0 WConclusions. Exceeding the power levels of a diode laser with a wavelength of 970 nm leads to the formation of carbonization of the surrounding tissues, to a damage of the vascular wall. In order to prevent bleeding, arteries with a diameter of more than 1.5 mm must be stitched. Small vessels with a diameter of less than 0.4 mm do not require preventive coagulation and can be coagulated during the incision with a laser fiber.

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