APPLICATION
Laser induced break down(LIBS) is a method of analysis of materials. It is a kind of emission spectroscopy, very easy to analyse many kinds of elements at the same time. Since it was introduced for analytical field in 1962, especially in these two decades, LIBS has developed very fast. Now it has been researched not only in LABS, but in many field as well, such as metallurgy, cultural heritage and archaeology. Spectrograph also plays important role in LIBS system, despite of laser and fast detectors.
light sources are very popular in many optical experiments, but many can’t provide monochromatic light or a short bandwidth light. Tunable Light Source (TLS) can match these requirements. It’s very easy to achieve high bright emission light or hight resolution monochromatic light with a diffraction system.
氧 (氮)化物荧光粉材料以其高发光效率、可被可见光有效激发、稳定性高和环境友好等诸多优点,在固体发光领域受到广泛重视。其中,稀土掺杂的荧光粉由于表现出较高的发光强度、较高的量子效率和优异的热稳定性,具有较好的应用前景。铕(Eu)元素在化合物中存在Eu2+和Eu3+两种价态。Eu2+发射峰位易受晶体场影响的,即基体或者参杂材料的改变(浓度、元素等),发射峰的强度会发生变化,发射中心会发生红移或者蓝移;Eu3+的发射峰是由其自身决定的,比较尖锐、峰位不受晶体场的影响。
钙钛矿(Perovskite)材料是一类有着与钛酸钙(CaTiO3)相同晶体结构的材料。 钙钛矿材料结构式一般为ABX3,其中A,B是两种阳离子,X 是阴离子。 近200年来,人们对钙钛矿材料的研究从未停止,元素周期表几乎所有的元素都可以占据晶格结构的位置组成钙钛矿。钙钛矿大家族里现已包括数百种物质,范围极为广泛,其中很多是人工合成的。 这类材料具有独特的魅力,其多变的晶体结构可以引申出众多的材料属性:可以是绝缘体、半导体、导体、超导体,可以具有铁电性、铁磁性,铁弹性、催化性、质子传导性、离子传导性、光电性。
概念解释:暗场显微(英文:Dark-field microscopy)或称暗视野显微(英文:Dark ground microscopy)描述光学显微和电子显微中的一种特殊显微手法,除去观测物体以外的光线或电子进入物镜,使目镜中观测到的视野背景是黑的,只有物体的边缘是亮的。利用这个方法能见到小至 4~200nm的微粒子,分辨率可比普通显微法高50倍。