Lead halide perovskites have attracted considerable attention as potential candidates for high-performance nano/microlasers,owing to their outstanding optical properties.However,the further development of perovskite m...Lead halide perovskites have attracted considerable attention as potential candidates for high-performance nano/microlasers,owing to their outstanding optical properties.However,the further development of perovskite microlaser arrays(especially based on polycrystalline thin films)produced by the conventional processing techniques is hindered by the chemical instability and surface roughness of the perovskite structures.Herein,we demonstrate a laser patterning of large-scale,highly crystalline perovskite single-crystal films to fabricate reproducible perovskite single-crystal-based microlaser arrays.Perovskite thin films were directly ablated by femtosecond-laser in multiple low-power cycles at a minimum machining line width of approximately 300 nm to realize high-precision,chemically clean,and repeatable fabrication of microdisk arrays.The surface impurities generated during the process can be washed away to avoid external optical loss due to the robustness of the single-crystal film.Moreover,the high-quality,large-sized perovskite single-crystal films can significantly improve the quality of microcavities,thereby realizing a perovskite microdisk laser with narrow linewidth(0.09 nm)and low threshold(5.1µJ/cm2).Benefiting from the novel laser patterning method and the large-sized perovskite single-crystal films,a high power and high color purity laser display with single-mode microlasers as pixels was successfully fabricated.Thus,this study may offer a potential platform for mass-scale and reproducible fabrication of microlaser arrays,and further facilitate the development of highly integrated applications based on perovskite materials.展开更多
We have developed Macadam’s theory to deal with RGB laser display, which can well describe the color gamut display system varying with the laser bandwidth. By calculating the volume of R¨osch–Macadam color soli...We have developed Macadam’s theory to deal with RGB laser display, which can well describe the color gamut display system varying with the laser bandwidth. By calculating the volume of R¨osch–Macadam color solid of laser display system under the Rec.2020 standard, we can obtain that the volume of chromatic stereoscopic at 30-nm laser spectral linewidth is about 90% of that at 1 nm laser spectral linewidth, which is important in laser display system to trade off the color gamut and the suppression of laser speckles. Moreover, we can also calculate the color gamut volume with different primary numbers and different primary wavelengths.展开更多
Laser phosphor display technology plays an important role in advanced display projection;however,it is a challenge in maintaining excellent color accuracy under high brightness due to the lack of red spectrum.Here,red...Laser phosphor display technology plays an important role in advanced display projection;however,it is a challenge in maintaining excellent color accuracy under high brightness due to the lack of red spectrum.Here,red-emitting Mg_(2)Al_(4)Si_(5)O_(18):Eu^(2+)ceramics as the phosphor wheel have been optimized in chemical compositions and texture orientation.The textured Mg_(2)Al_(4)Si_(5)O_(18):Eu^(2+)ceramics have high transparency and spot limiting ability,accordingly,the ceramic wheel outputs 1,184 lm of ultra-bright red light under 50 W/mm^(2) laser power density.Moreover,the red spectral utilization(over 600 nm)of textured Mg_(2)Al_(4)Si_(5)O_(18):Eu^(2+)ceramics is 2.17 times that of traditional Y_(3)Al_(5)O_(12):Ce^(3+)phosphor wheel.The red-emitting textured Mg_(2)Al_(4)Si_(5)O_(18):Eu^(2+)cordierite ceramic herein enables an improved light-color saturation experience,and it is potential in the next-generation laser phosphor display applications.展开更多
Laser display technology is the most promising display technology in the market and is widely used in many fields. However, laser speckle has been troubling the application and expansion of this technology in some fie...Laser display technology is the most promising display technology in the market and is widely used in many fields. However, laser speckle has been troubling the application and expansion of this technology in some fields. In order to better evaluate the speckle, speckle measurement methods must be studied. In this study, a dynamic measurement method for laser speckles is proposed according to the optical superposition characteristics of speckle, which can reduce the influence of non-coherent factors on the speckle measurement results. The feasibility of the dynamic speckle measurement method is verified by designing an experimental scheme.展开更多
AIM：To compare the efficacy of single-session 360-degree selective laser trabeculoplasty（SLT） for reduction of intraocular pressure（IOP） in patients with pseudoexfoliative glaucoma（PXFG） and primary open angle ...AIM：To compare the efficacy of single-session 360-degree selective laser trabeculoplasty（SLT） for reduction of intraocular pressure（IOP） in patients with pseudoexfoliative glaucoma（PXFG） and primary open angle glaucoma（POAG）.· METHODS：This is a single-center,prospective,nonrandomized comparative study.Patients older than 18 years of age with uncontrolled PXFG or POAG eyes requiring additional therapy while on maximally tolerated IOP-lowering medications were included.The primary outcome measure changed in IOP from baseline.Success was defined as IOP reduction ≥20%from baseline without any additional IOP-lowering medication.All patients were examined at 1d,1wk,1,3,6,9,12 mo after SLT.· RESULTS：Nineteen patients（20 eyes） with PXFG and27 patients（28 eyes） with POAG were included in the study.In the visual fields mean deviation was-2.88（±1.67）in the POAG and-3.1（±1.69） in the PXFG groups（P=0.3）.The mean（±SD） IOP was 22.9（±3.7） mm Hg in the POAG group and 25.7（±4.4） mm Hg in the PXFG group at baseline and decreased to 18.4（±3.2） and 18.0（±3.9） mm Hg in the POAG group（P〈0.001 and P=0.02）,and to 17.9（±4.0） and 21.0（±6.6） mm Hg in the PXFG group（P〈0.001 and P=0.47） at 6 and 12 mo,respectively.The number of medications was 2.6（±0.8） in the POAG group and 2.5（±0.8） in the PXFG group at baseline,and did not change at all follow-up visits in both groups（P =0.16 in POAG and 0.57 in PXFG）.Based on Kaplan-Meier survival analysis,the success rate was 75%in the POAG group compared to 94.1%in the PXFG group（P=0.08;Log-rank test） at 6mo,and 29.1%and 25.0%at 12 mo,respectively（P=0.9;Log-rank）.· CONCLUSION：The 360-degree SLT is an effective and well-tolerated therapeutic modality in patients with POAG and PXFG by reducing IOP without any change in number of medications.The response was more pronounced early in the postoperative period in patients with PXFG whereas there was no statistically significant difference at 12-month follow-up. 〈/tr〉展开更多
<abstract>Aim: To study the histologic changes of the vas deferens following Nd: YAG laser irradiation. Methods: Intravasal laser irradiation was given to (i) 52 segments of rabbit (laser dosage: 2 seconds at 40...<abstract>Aim: To study the histologic changes of the vas deferens following Nd: YAG laser irradiation. Methods: Intravasal laser irradiation was given to (i) 52 segments of rabbit (laser dosage: 2 seconds at 40 W-50 W) and 16 segments of human (3 seconds at 45 W-55 W) vas deferens in vitro, (ii) 25 rabbit vasa (2 seconds-2.5 seconds at 40 W-45 W) in vivo and (iii) 2 human vasa (3 seconds at 55W) in vivo. Segments of vasa were removed from the in vivo irradiated vasa deferentia 15 days-180 days (rabbit) or 15 days (man) after the exposure. All vas segments were embedded in methacrylate resin. Serial sections (thickness 25μm-30μm) were obtained and observed under a light microscope. Results: (i) Laser-induced damage reached the muscularis layer in 27 % and 94 % of the rabbit and human vas segments in vitro, respectively, (ii) Fourteen of the 25 in vivo rabbit vasa were completely occluded by fibrous tissue and the longer the time interval after treatment, the more likely was the vas occluded. Those unoccluded vasa had either a normal histology or a mucosal damage, (iii) One in vivo human vas was almost completely occluded by the fibrous tissue but the other had a relatively large lumen packed with sperm granulomatous tissue and partial destruction of the smooth muscle layer. Conclusion: Laser irradiation can induce long-term vas occlusion; for rapid occlusion, laser doses just completely destroying the mucosal layer will be advisable.展开更多
Laser-based displays have attracted much attention owing to large-size screen and full-color gamut compared with other displays such as liquid crystal display and light emitting diode. However, there exists a phenomen...Laser-based displays have attracted much attention owing to large-size screen and full-color gamut compared with other displays such as liquid crystal display and light emitting diode. However, there exists a phenomenon, speckle, limits the applications of laser display because of the high coherence of laser. In this work, we developed an electrically injected 6xx nm dual-emitter laser which combines the low-spatial coherence with the high-power. The output power of the dual-emitter laser exceeds 500 mW under 20?C pulse operation. The single emitter consists of D-shaped section used to obtain more independent spatial modes thus reduces coherence and a stripe area to obtain the high power. The radius of the D-shaped cavity is 500 μm and the length of stripe is 1000 μm. We used the standard photolithography and inductively coupled plasma (ICP) process to fabricate the device. The speckle contrast was measured to be 5%. It exhibits a great potential of reducing speckle from the source directly for laser display.展开更多
The sulfides of transitional metals chromium[1-3] and iron[4] are of great importance inmaterial and biology sciences due to their characteristic structures and properties．So the studyon the properties of Cr－S and F...The sulfides of transitional metals chromium[1-3] and iron[4] are of great importance inmaterial and biology sciences due to their characteristic structures and properties．So the studyon the properties of Cr－S and Fe－S clusters will give many contributions to the understandingof physical and chemical behavior of those compounds．展开更多
The satellite laser ranging （SLR） data quality from the COMPASS was analyzed, and the difference between curve recognition in computer vision and pre-process of SLR data finally proposed a new algorithm for SLR was ...The satellite laser ranging （SLR） data quality from the COMPASS was analyzed, and the difference between curve recognition in computer vision and pre-process of SLR data finally proposed a new algorithm for SLR was discussed data based on curve recognition from points cloud is proposed. The results obtained by the new algorithm are 85 % （or even higher） consistent with that of the screen displaying method, furthermore, the new method can process SLR data automatically, which makes it possible to be used in the development of the COMPASS navigation system.展开更多
基金the support from the National Natural Science Foundation of China (No. 61925506)the Natural Science Foundation of Shanghai (No. 20JC1414605)+1 种基金Hangzhou Science and Technology Bureau of Zhejiang Province (No. TD2020002)the Academic/Technology Research Leader Program of Shanghai (23XD1404500)
文摘Lead halide perovskites have attracted considerable attention as potential candidates for high-performance nano/microlasers,owing to their outstanding optical properties.However,the further development of perovskite microlaser arrays(especially based on polycrystalline thin films)produced by the conventional processing techniques is hindered by the chemical instability and surface roughness of the perovskite structures.Herein,we demonstrate a laser patterning of large-scale,highly crystalline perovskite single-crystal films to fabricate reproducible perovskite single-crystal-based microlaser arrays.Perovskite thin films were directly ablated by femtosecond-laser in multiple low-power cycles at a minimum machining line width of approximately 300 nm to realize high-precision,chemically clean,and repeatable fabrication of microdisk arrays.The surface impurities generated during the process can be washed away to avoid external optical loss due to the robustness of the single-crystal film.Moreover,the high-quality,large-sized perovskite single-crystal films can significantly improve the quality of microcavities,thereby realizing a perovskite microdisk laser with narrow linewidth(0.09 nm)and low threshold(5.1µJ/cm2).Benefiting from the novel laser patterning method and the large-sized perovskite single-crystal films,a high power and high color purity laser display with single-mode microlasers as pixels was successfully fabricated.Thus,this study may offer a potential platform for mass-scale and reproducible fabrication of microlaser arrays,and further facilitate the development of highly integrated applications based on perovskite materials.
基金Project supported by the National Key Research and Development Program of China(Grant No.2016YFB0401900)the Major Science and Technology Special Project in Anhui Province,China(Grant No.17030901001)
文摘We have developed Macadam’s theory to deal with RGB laser display, which can well describe the color gamut display system varying with the laser bandwidth. By calculating the volume of R¨osch–Macadam color solid of laser display system under the Rec.2020 standard, we can obtain that the volume of chromatic stereoscopic at 30-nm laser spectral linewidth is about 90% of that at 1 nm laser spectral linewidth, which is important in laser display system to trade off the color gamut and the suppression of laser speckles. Moreover, we can also calculate the color gamut volume with different primary numbers and different primary wavelengths.
基金This research was supported by National Natural Science Foundations of China(51972118)the Fundamental Research Funds for the Central Universities(2023ZYGXZR002)the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(2017BT01X137).
文摘Laser phosphor display technology plays an important role in advanced display projection;however,it is a challenge in maintaining excellent color accuracy under high brightness due to the lack of red spectrum.Here,red-emitting Mg_(2)Al_(4)Si_(5)O_(18):Eu^(2+)ceramics as the phosphor wheel have been optimized in chemical compositions and texture orientation.The textured Mg_(2)Al_(4)Si_(5)O_(18):Eu^(2+)ceramics have high transparency and spot limiting ability,accordingly,the ceramic wheel outputs 1,184 lm of ultra-bright red light under 50 W/mm^(2) laser power density.Moreover,the red spectral utilization(over 600 nm)of textured Mg_(2)Al_(4)Si_(5)O_(18):Eu^(2+)ceramics is 2.17 times that of traditional Y_(3)Al_(5)O_(12):Ce^(3+)phosphor wheel.The red-emitting textured Mg_(2)Al_(4)Si_(5)O_(18):Eu^(2+)cordierite ceramic herein enables an improved light-color saturation experience,and it is potential in the next-generation laser phosphor display applications.
基金supported by the National Natural Science Foundation of China (No.62076160)the Natural Science Foundation of Shanghai (No.21ZR1424700)。
文摘Laser display technology is the most promising display technology in the market and is widely used in many fields. However, laser speckle has been troubling the application and expansion of this technology in some fields. In order to better evaluate the speckle, speckle measurement methods must be studied. In this study, a dynamic measurement method for laser speckles is proposed according to the optical superposition characteristics of speckle, which can reduce the influence of non-coherent factors on the speckle measurement results. The feasibility of the dynamic speckle measurement method is verified by designing an experimental scheme.
文摘AIM：To compare the efficacy of single-session 360-degree selective laser trabeculoplasty（SLT） for reduction of intraocular pressure（IOP） in patients with pseudoexfoliative glaucoma（PXFG） and primary open angle glaucoma（POAG）.· METHODS：This is a single-center,prospective,nonrandomized comparative study.Patients older than 18 years of age with uncontrolled PXFG or POAG eyes requiring additional therapy while on maximally tolerated IOP-lowering medications were included.The primary outcome measure changed in IOP from baseline.Success was defined as IOP reduction ≥20%from baseline without any additional IOP-lowering medication.All patients were examined at 1d,1wk,1,3,6,9,12 mo after SLT.· RESULTS：Nineteen patients（20 eyes） with PXFG and27 patients（28 eyes） with POAG were included in the study.In the visual fields mean deviation was-2.88（±1.67）in the POAG and-3.1（±1.69） in the PXFG groups（P=0.3）.The mean（±SD） IOP was 22.9（±3.7） mm Hg in the POAG group and 25.7（±4.4） mm Hg in the PXFG group at baseline and decreased to 18.4（±3.2） and 18.0（±3.9） mm Hg in the POAG group（P〈0.001 and P=0.02）,and to 17.9（±4.0） and 21.0（±6.6） mm Hg in the PXFG group（P〈0.001 and P=0.47） at 6 and 12 mo,respectively.The number of medications was 2.6（±0.8） in the POAG group and 2.5（±0.8） in the PXFG group at baseline,and did not change at all follow-up visits in both groups（P =0.16 in POAG and 0.57 in PXFG）.Based on Kaplan-Meier survival analysis,the success rate was 75%in the POAG group compared to 94.1%in the PXFG group（P=0.08;Log-rank test） at 6mo,and 29.1%and 25.0%at 12 mo,respectively（P=0.9;Log-rank）.· CONCLUSION：The 360-degree SLT is an effective and well-tolerated therapeutic modality in patients with POAG and PXFG by reducing IOP without any change in number of medications.The response was more pronounced early in the postoperative period in patients with PXFG whereas there was no statistically significant difference at 12-month follow-up. 〈/tr〉
文摘<abstract>Aim: To study the histologic changes of the vas deferens following Nd: YAG laser irradiation. Methods: Intravasal laser irradiation was given to (i) 52 segments of rabbit (laser dosage: 2 seconds at 40 W-50 W) and 16 segments of human (3 seconds at 45 W-55 W) vas deferens in vitro, (ii) 25 rabbit vasa (2 seconds-2.5 seconds at 40 W-45 W) in vivo and (iii) 2 human vasa (3 seconds at 55W) in vivo. Segments of vasa were removed from the in vivo irradiated vasa deferentia 15 days-180 days (rabbit) or 15 days (man) after the exposure. All vas segments were embedded in methacrylate resin. Serial sections (thickness 25μm-30μm) were obtained and observed under a light microscope. Results: (i) Laser-induced damage reached the muscularis layer in 27 % and 94 % of the rabbit and human vas segments in vitro, respectively, (ii) Fourteen of the 25 in vivo rabbit vasa were completely occluded by fibrous tissue and the longer the time interval after treatment, the more likely was the vas occluded. Those unoccluded vasa had either a normal histology or a mucosal damage, (iii) One in vivo human vas was almost completely occluded by the fibrous tissue but the other had a relatively large lumen packed with sperm granulomatous tissue and partial destruction of the smooth muscle layer. Conclusion: Laser irradiation can induce long-term vas occlusion; for rapid occlusion, laser doses just completely destroying the mucosal layer will be advisable.
文摘Laser-based displays have attracted much attention owing to large-size screen and full-color gamut compared with other displays such as liquid crystal display and light emitting diode. However, there exists a phenomenon, speckle, limits the applications of laser display because of the high coherence of laser. In this work, we developed an electrically injected 6xx nm dual-emitter laser which combines the low-spatial coherence with the high-power. The output power of the dual-emitter laser exceeds 500 mW under 20?C pulse operation. The single emitter consists of D-shaped section used to obtain more independent spatial modes thus reduces coherence and a stripe area to obtain the high power. The radius of the D-shaped cavity is 500 μm and the length of stripe is 1000 μm. We used the standard photolithography and inductively coupled plasma (ICP) process to fabricate the device. The speckle contrast was measured to be 5%. It exhibits a great potential of reducing speckle from the source directly for laser display.
文摘The sulfides of transitional metals chromium[1-3] and iron[4] are of great importance inmaterial and biology sciences due to their characteristic structures and properties．So the studyon the properties of Cr－S and Fe－S clusters will give many contributions to the understandingof physical and chemical behavior of those compounds．
文摘The satellite laser ranging （SLR） data quality from the COMPASS was analyzed, and the difference between curve recognition in computer vision and pre-process of SLR data finally proposed a new algorithm for SLR was discussed data based on curve recognition from points cloud is proposed. The results obtained by the new algorithm are 85 % （or even higher） consistent with that of the screen displaying method, furthermore, the new method can process SLR data automatically, which makes it possible to be used in the development of the COMPASS navigation system.
