We present the workflow of the design, realization and testing of deformable mirrors suitable for high power diode pumped solid-state lasers. It starts with the study of the aberration to be corrected, and then it con...We present the workflow of the design, realization and testing of deformable mirrors suitable for high power diode pumped solid-state lasers. It starts with the study of the aberration to be corrected, and then it continues with the design of the actuators position and characteristic. In this paper, we present and compare three deformable mirrors realized for multi-J level laser facilities. We show that with the same design concept it is possible to realize deformable mirrors for other types of lasers. As an example, we report the realization of a deformable mirror for femtosecond lasers and for a CW CO_2 laser.展开更多
We present a diode-pumped, electro-optically Q-switched Tm:YAG laser with a cryogenically cooled laser crystal at120 K. Output pulses of up to 2.55 mJ and 650 ns duration were demonstrated in an actively Q-switched co...We present a diode-pumped, electro-optically Q-switched Tm:YAG laser with a cryogenically cooled laser crystal at120 K. Output pulses of up to 2.55 mJ and 650 ns duration were demonstrated in an actively Q-switched configuration with a repetition rate of 1 Hz. By using cavity dumping the pulse duration was shortened to 18 ns with only a slightly lower output energy of 2.22 mJ. Furthermore, using a simplified rate equation model, we discuss design constraints on the pump fluence in a pulse pump approach for Tm:YAG to maximize the energy storage capability at a given pump power.展开更多
We present the results of performance modeling of a diode-pumped solid-state HiLASE laser designed for use in inertial fusion energy power plants. The main amplifier concept is based on a He-gas-cooled multi-slab arch...We present the results of performance modeling of a diode-pumped solid-state HiLASE laser designed for use in inertial fusion energy power plants. The main amplifier concept is based on a He-gas-cooled multi-slab architecture similar to that employed in Mercury laser system. Our modeling quantifies the reduction of thermally induced phase aberrations and average depolarization in Yb3+:YAG slabs by a combination of helium cryogenic cooling and properly designed(doping/width) cladding materials.展开更多
Development of high energy laser sources with nanosecond pulses at several hertz values for repetition rate has been very attractive in recent years due to their great potential for practical applications. With the re...Development of high energy laser sources with nanosecond pulses at several hertz values for repetition rate has been very attractive in recent years due to their great potential for practical applications. With the recent advancement in fabricating large size laser quality transparent ceramics, diode pumped solid-state laser generating pulse energy of 100 J at 10 Hz has been recently realized at HiLASE center using Yb:YAG ceramic with Cr:YAG cladding. This review discusses Yb based high energy lasers, specific laser geometries for efficient thermal management and the role of transparent ceramics in such diode pumped high-energy-class solid-state lasers around the world.展开更多
An overview of the Czech national R&D project HiLASE(High average power pulsed laser) is presented. The project focuses on the development of advanced high repetition rate, diode pumped solid state laser(DPSSL) sy...An overview of the Czech national R&D project HiLASE(High average power pulsed laser) is presented. The project focuses on the development of advanced high repetition rate, diode pumped solid state laser(DPSSL) systems with energies in the range from mJ to 100 J and repetition rates in the range from 10 Hz to 100 kHz. Some applications of these lasers in research and hi-tech industry are also presented.展开更多
Further advancement of high-energy pulsed lasers requires a parallel development of appropriate optical components.Several different optical components, such as mirrors and antireflection-coated windows, which are ess...Further advancement of high-energy pulsed lasers requires a parallel development of appropriate optical components.Several different optical components, such as mirrors and antireflection-coated windows, which are essential for the design of Hi LASE high average power lasers were tested. The following paper summarizes results on the measurements of laser-induced damage threshold of such components, and clearly shows their capabilities and limitations for such a demanding application.展开更多
BACKGROUND Enteric-coated medications are supposed to pass intact through the gastric environment and to release the drug content into the small intestine or the colon.Before dissolution of the enteric coating,they ma...BACKGROUND Enteric-coated medications are supposed to pass intact through the gastric environment and to release the drug content into the small intestine or the colon.Before dissolution of the enteric coating,they may appear hyperdense on computed tomography(CT).Unfortunately,few reports have been published on this topic so far.In this case report,the hyperdense appearance on contrastenhanced CT of an enteric-coated mesalamine tablet was initially misinterpreted as a jejunal gastrointestinal stromal tumor(GIST).CASE SUMMARY An asymptomatic 81-year-old male patient,who had undergone laparoscopic right nephrectomy four years earlier for stage 1 renal carcinoma,was diagnosed with a jejunal GIST at the 4-year follow-up thoraco-abdominal CT scan.He was referred to our hub hospital for gastroenterological evaluation,and subsequently underwent 18-fluorodeoxyglucose positron emission tomography,abdominal magnetic resonance imaging,and video capsule endoscopy.None of these examinations detected any lesion of the small intestine.After reviewing all the CT images in a multidisciplinary setting,the panel estimated that the hyperdense jejunal image was consistent with a tablet rather than a GIST.The tablet was an 800 mg delayed-release enteric-coated oral mesalamine tablet(Asacol®),which had been prescribed for non-specific colitis,while not informing the hospital physicians.CONCLUSION Delayed-release oral mesalamine(Asacol®),like other enteric-coated medications,can appear as a hyperdense image on a CT scan,mimicking a small intestinal GIST.Therefore,adetailed knowledge of the patients’medications and a multidisciplinary review of the images areessential.展开更多
Faraday effect measurements of holmium oxide(Ho_2O_3) ceramics-based magneto-optical materials, highly potential material candidates for high-energy laser Faraday isolators, are presented in this paper. Temperature de...Faraday effect measurements of holmium oxide(Ho_2O_3) ceramics-based magneto-optical materials, highly potential material candidates for high-energy laser Faraday isolators, are presented in this paper. Temperature dependence of the Verdet constant of nondoped Ho_2O_3 ceramics was measured for temperatures 15–305 K at 1.064 μm wavelength.The Verdet constant dispersion for wavelengths 0.5–1 μm and 1.064 μm was measured for both nondoped Ho_2O_3 ceramics and Ho_2O_3 ceramics doped with terbium Tb3+(0.2 at. %) and cerium Ce3+(0.1 at. %) ions. The results suggest that the relatively low level of doping of Ho_2O_3 with these ions has no significant boosting impact on the Faraday effect. Therefore, other compositions of Ho_2O_3 ceramics-based magneto-optical materials, as well as various doping concentrations, should be further examined.展开更多
基金co-financed by the European Regional Development Fundthe European Social Fund+1 种基金the state budget of the Czech Republic(project HiLASE:CZ.1.05/2.1.00/01.0027,project DPSSLasers:CZ.1.07/2.3.00/20.0143)partially supported by the grant RVO 68407700
文摘We present the workflow of the design, realization and testing of deformable mirrors suitable for high power diode pumped solid-state lasers. It starts with the study of the aberration to be corrected, and then it continues with the design of the actuators position and characteristic. In this paper, we present and compare three deformable mirrors realized for multi-J level laser facilities. We show that with the same design concept it is possible to realize deformable mirrors for other types of lasers. As an example, we report the realization of a deformable mirror for femtosecond lasers and for a CW CO_2 laser.
基金funding from the European Union’s Horizon 2020 research and innovation programme(871124 Laserlab-Europe and 739573)the Thuringian Ministry for Economic Affairs,Science and Digital Society(2016FE9058)+2 种基金Bundesministerium für Bildung und Forschung(BMBF)(03ZIK445,05P15SJFA1,03Z1H531,03VNE2068D)the European Regional Development Fund and the state budget of the Czech Republic(project Hi LASE CZ.02.1.01/0.0/0.0/15006/0000674)the Ministry of Education,Youth and Sports of the Czech Republic(NPU I Project No.LO1602)。
文摘We present a diode-pumped, electro-optically Q-switched Tm:YAG laser with a cryogenically cooled laser crystal at120 K. Output pulses of up to 2.55 mJ and 650 ns duration were demonstrated in an actively Q-switched configuration with a repetition rate of 1 Hz. By using cavity dumping the pulse duration was shortened to 18 ns with only a slightly lower output energy of 2.22 mJ. Furthermore, using a simplified rate equation model, we discuss design constraints on the pump fluence in a pulse pump approach for Tm:YAG to maximize the energy storage capability at a given pump power.
基金the support of the Czech Republic’s Ministry of Education, Youth and Sports to the HiLASE (CZ.1.05/2.1.00/01.0027), DPSSLasers (CZ.1.07/2.3.00/ 20.0143), and Postdok (CZ.1.07/2.3.00/30.0057) projects, co-financed by the European Regional Development Fund. This research was supported by grant RVO 68407700
文摘We present the results of performance modeling of a diode-pumped solid-state HiLASE laser designed for use in inertial fusion energy power plants. The main amplifier concept is based on a He-gas-cooled multi-slab architecture similar to that employed in Mercury laser system. Our modeling quantifies the reduction of thermally induced phase aberrations and average depolarization in Yb3+:YAG slabs by a combination of helium cryogenic cooling and properly designed(doping/width) cladding materials.
基金co-financed by the European Regional Development Fundthe state budget of the Czech Republic (project HiLASE CoE: Grant No. CZ.02.1.01/0.0/ 0.0/15 006/0000674)+1 种基金the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 739573the Ministry of Education, Youth and Sports of the Czech Republic (Programmes NPU I Project No. LO1602, and Large Research Infrastructure Project No. LM2015086)
文摘Development of high energy laser sources with nanosecond pulses at several hertz values for repetition rate has been very attractive in recent years due to their great potential for practical applications. With the recent advancement in fabricating large size laser quality transparent ceramics, diode pumped solid-state laser generating pulse energy of 100 J at 10 Hz has been recently realized at HiLASE center using Yb:YAG ceramic with Cr:YAG cladding. This review discusses Yb based high energy lasers, specific laser geometries for efficient thermal management and the role of transparent ceramics in such diode pumped high-energy-class solid-state lasers around the world.
基金the support of the Czech Republic’s Ministry of Education, Youth and Sports to the HiLASE (CZ.1.05/2.1.00/01.0027)DPSSLasers (CZ.1.07/2.3.00/ 20.0143)+2 种基金Postdok (CZ.1.07/2.3.00/30.0057) projectsco-financed by the European Regional Development Fundpartially supported by grant RVO 68407700
文摘An overview of the Czech national R&D project HiLASE(High average power pulsed laser) is presented. The project focuses on the development of advanced high repetition rate, diode pumped solid state laser(DPSSL) systems with energies in the range from mJ to 100 J and repetition rates in the range from 10 Hz to 100 kHz. Some applications of these lasers in research and hi-tech industry are also presented.
基金funding from LASERLAB-EUROPE (grant agreement no.284464,EC’s Seventh Framework Programme)co-financed by the European Regional Development Fund+2 种基金the European Social Fundthe state budget of the Czech Republic (project HiLASE:CZ.1.05/ 2.1.00/01.0027,project DPSSLasers:CZ.1.07/2.3.00/20.0143,project Postdok:CZ.1.07/2.3.00/30.0057)partially supported by the grant RVO 68407700
文摘Further advancement of high-energy pulsed lasers requires a parallel development of appropriate optical components.Several different optical components, such as mirrors and antireflection-coated windows, which are essential for the design of Hi LASE high average power lasers were tested. The following paper summarizes results on the measurements of laser-induced damage threshold of such components, and clearly shows their capabilities and limitations for such a demanding application.
文摘BACKGROUND Enteric-coated medications are supposed to pass intact through the gastric environment and to release the drug content into the small intestine or the colon.Before dissolution of the enteric coating,they may appear hyperdense on computed tomography(CT).Unfortunately,few reports have been published on this topic so far.In this case report,the hyperdense appearance on contrastenhanced CT of an enteric-coated mesalamine tablet was initially misinterpreted as a jejunal gastrointestinal stromal tumor(GIST).CASE SUMMARY An asymptomatic 81-year-old male patient,who had undergone laparoscopic right nephrectomy four years earlier for stage 1 renal carcinoma,was diagnosed with a jejunal GIST at the 4-year follow-up thoraco-abdominal CT scan.He was referred to our hub hospital for gastroenterological evaluation,and subsequently underwent 18-fluorodeoxyglucose positron emission tomography,abdominal magnetic resonance imaging,and video capsule endoscopy.None of these examinations detected any lesion of the small intestine.After reviewing all the CT images in a multidisciplinary setting,the panel estimated that the hyperdense jejunal image was consistent with a tablet rather than a GIST.The tablet was an 800 mg delayed-release enteric-coated oral mesalamine tablet(Asacol®),which had been prescribed for non-specific colitis,while not informing the hospital physicians.CONCLUSION Delayed-release oral mesalamine(Asacol®),like other enteric-coated medications,can appear as a hyperdense image on a CT scan,mimicking a small intestinal GIST.Therefore,adetailed knowledge of the patients’medications and a multidisciplinary review of the images areessential.
基金supported by JSPS KAKENHI (Grant No. 15KK0245)the support and under the auspices of the National Institute for Fusion Science (KEIN1608)+3 种基金co-financed by the European Regional Development Fundthe state budget of the Czech Republic (project Hi LASE Co E: Grant No. CZ.02.1.010.00.015 0060000674)by the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 739573supported by the Ministry of Education, Youth and Sports of the Czech Republic (Programmes NPU I Project No. LO1602, and Large Research Infrastructure Project No. LM2015086)
文摘Faraday effect measurements of holmium oxide(Ho_2O_3) ceramics-based magneto-optical materials, highly potential material candidates for high-energy laser Faraday isolators, are presented in this paper. Temperature dependence of the Verdet constant of nondoped Ho_2O_3 ceramics was measured for temperatures 15–305 K at 1.064 μm wavelength.The Verdet constant dispersion for wavelengths 0.5–1 μm and 1.064 μm was measured for both nondoped Ho_2O_3 ceramics and Ho_2O_3 ceramics doped with terbium Tb3+(0.2 at. %) and cerium Ce3+(0.1 at. %) ions. The results suggest that the relatively low level of doping of Ho_2O_3 with these ions has no significant boosting impact on the Faraday effect. Therefore, other compositions of Ho_2O_3 ceramics-based magneto-optical materials, as well as various doping concentrations, should be further examined.
