Author Affiliations
Abstract
School of Artificial Intelligence, Optics and Electronics (iOPEN), Northwestern Polytechnical University, Xi’an, Shaanxi 710072, P. R. China
The miniaturized femtosecond laser in near infrared-II region is the core equipment of three-photon microscopy. In this paper, we design a compact and robust illumination source that emits dual-color linearly polarized light for three-photon microscopy. Based on an all-polarization-maintaining passive mode-locked fiber laser, we shift the center wavelength of the pulses to the 1.7μm band utilizing cascade Raman effect, thereby generate dual-wavelength pulses. To enhance clarity, the two wavelengths are separated through the graded-index multimode fiber. Then we obtain the dual-pulse sequences with 1639.4nm and 1683.7nm wavelengths, 920fs pulse duration, and 23.75MHz pulse repetition rate. The average power of the signal is 53.64mW, corresponding to a single pulse energy of 2.25nJ. This illumination source can be further amplified and compressed for three-photon fluorescence imaging, especially dual-color three-photon fluorescence imaging, making it an ideal option for biomedical applications.
Three-photon fluorescence imaging illumination source dual-wavelength femtosecond pulse cascaded Raman effect graded-index multimode fiber Journal of Innovative Optical Health Sciences
2023, 16(5): 2241005
Author Affiliations
Abstract
Grünberg Research Centre, College of Telecommunications and Information Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210003, China
To date, fluorescence imaging systems have all relied on at least one beam splitter (BS) to ensure the separation of excitation light and fluorescence. Here, we reported multi-layer long pass filter integrated GaN LED. It is considered as the potential source for imaging systems. Experimental results indicate that the GaN LED shows blue emission peaked at 470.3 nm and can be used to excite dye materials. Integrating with a long pass filter (550 nm), the light source can be used to establish a real-time fluorescence detection for dyes that emit light above 550 nm. More interestingly, with this source, a real-time imaging system with signature words written with the dyes, such as ‘N J U P T’, can be converted into CCD images. This work may lead to a new strategy for integrating light sources and BS mirrors to build mini and smart fluorescence imaging systems.
GaN LED self-filtering illumination source fluorescence imaging Chinese Optics Letters
2023, 21(1): 011101
1 长春理工大学 理学院，吉林 长春 130022
2 吉林省科学技术信息研究所，吉林 长春 130000
通过建立光电热(PET)模型，研究了发光二极管(LED)光源相关色温(CCT)的模型预测控制方法，实现了多主色LED光源的相关色温控制。首先，提出了热平衡状态稳定假设和修正的非对称高斯函数作为基函数的假设; 根据软模型建模思路,用最小二乘估计求解各个模型参量的回归子模型，分析光谱敏感系数曲线随CCT变化的关系。 然后，通过重力线法调试出在3 000，4 500和6 500 K 下3个常用色温点处所需的电流控制量。最后，在调设好的电流控制量上加以一定的无规则扰动产生一组验证数据，用于评价模型精度。实验结果表明: 建立的多主色LED光源的PET数学模型能够很好地通过电流控制量和环境温度来预测LED的热沉温度和多主色合成光谱功率分布函数，进而能够预测控制色温，具有很好的模型精度。得到的色度坐标预测精度优于±0.005，CCT预测精度优于±150 K。提出的基于模型的控制方法不仅适用于常用LED光源的CCT调控，还可推广到更多通道的LED光源的色度及CCT控制中。
照明光源 多主色发光二极管 相关色温 光电热模型 illumination source multi-primary color Light Emission Diode(LED) correlated color temperature photo-electro-thermal model
中国海洋大学 信息科学与工程学院，山东 青岛 266100
基于制作全息灯箱背光源的需要，从色度上分析研究了发光二极管用于彩色全息图照明的可行性，对使用发光二极管和定向照明卤钨灯照明再现的彩色全息图进行了色度测量与评价.实验测量并计算了发光二极管与卤钨灯光谱功率分布RGB成分比，给出了在CIE1976均匀颜色空间中两种光源再现图像与原图像之间的色差.结果表明， 发光二极管用作彩色全息图照明光源是可行的，可以作为全息灯箱背光源.
视觉光学 照明光源 色度 全息 Visual optics Illumination source Chrominance LED LED Holography
