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981.
982.
提出了一种用于高层大气风场探测的改型大光程差Sagnac干涉仪,论述了其基本原理和分光机理;分析了空间光线在改型大光程差Sagnac干涉仪中的传播路径;利用空间几何方法,通过分析空间直线与其投影之间的关系,给出了入射光线绕入射界面法线旋转360°范围内,从任意方向以任意角度入射时,改型大光程差Sagnac干涉仪的光程差及横向剪切量的精确表达式,较目前文献所报道的只给出入射面与纸平面平行时光程差与横向剪切量的计算具有更加普遍的指导意义.为改型大光程差Sagnac干涉仪的设计、研制提供了重要的理论依据和实践指
关键词:
高层大气风场探测
改型大光程差Sagnac干涉仪
横向剪切量 相似文献
983.
984.
设计了一种新的光纤菲佐气体压力传感器,结合波分复用技术和空间频率复用技术,实现了不同腔长的光纤菲佐气体压力传感器的复用.给出了该复用系统的结构,阐述了其工作原理,最后利用实验验证了该方法的可行性.针对该系统中的串扰问题提出了基于参数化谱估计的Pisarenko谐波分解方案,使可复用的传感器腔长差降至100 μm左右,大大提高了系统的复用能力.实验结果表明:该系统在单个传感器气体压力分辨率达0.76% F.S(量程为0~150 kPa),复用的传感器数目可达80个以上,可满足实际工程应用中多点气压测量的需要. 相似文献
985.
986.
从几何光学出发,推导了毛细管干涉仪的从柱面透镜到接收屏的光线的光程.对光线追迹模拟,结果表明毛细管干涉仪的干涉条纹的形成可用双光束的干涉来解释.从柱面不同位置入射的两条光线可能具有相同的光程,而且从柱面透镜不同位置出发的两条光线可能到达接收屏的同一点,当它们满足相干条件时,就会形成干涉条纹.建立了干涉条纹的计算机模拟程序, 模拟了毛细管中液体折射率、毛细管内径、外径对干涉条纹的影响. 结果表明实验中应使用薄壁毛细管, 由于干涉条纹对柱面透镜到毛细管之间的距离非常敏感, 为提高精度, 建议在实验中用已知折射率的标样来确定这一距离. 相似文献
987.
Experimental study of a semiconductor laser diode having a Mach–Zehnder interferometer in the cavity
The performance of a semiconductor laser diode that has an asymmetric Mach–Zehnder interferometer all-optical switch in the cavity has been studied experimentally. This novel device was designed to be free from clock pulse insertion, since mode-locked optical pulses are generated internally and change the balance of the interferometer periodically. The device was fabricated using a InGaAsP/InP buried heterostructure and the primary optical properties of the device were investigated. Lasing characteristics that were peculiar to the twin-cavity structure were observed, i.e., continuous-wave lasing power oscillation in relation to the injection current balance between the two arms, and cyclic changes in the single/multiple emission peaks as a function of bias voltage at the saturable absorber. Electrical spectrum analysis indicated 40 GHz modulation of lasing output from the twin-cavity laser. 相似文献
988.
We present the use of a fiber optic Sagnac interferometer incorporating one and two fiber optic ring resonators to characterize experimentally the optical switching behaviors. These prototypes were formed by the Sagnac interferometer and serially connected to the ring resonators. The input optical signal was launched via one end of the interferometer, where the polarization control was employed to obtain the maximum optical transmission power. Results obtained have shown that the increasing in switching time (i.e. narrower spectral width) and power can be achieved. 相似文献
989.
A Mach–Zehnder interferometer (MZI) which is used as a wavelength-spacing tunable comb filter in a fiber ring laser is built by employing an optical variable delay line (OVDL). Stable multi-wavelength semiconductor optical amplifier (SOA)-fiber ring laser based on an SOA and the MZI comb filter is achieved. Wavelength spacing can be continuously tuned by adjusting the OVDL and, as an example, multi-wavelength lasing with the wavelength spacing of 0.4, 0.8, or 1.6 nm is demonstrated. The output of the proposed multi-wavelength SOA-fiber ring laser is quite stable at room temperature and the output spectrum can be adjusted by controlling the bias current of the SOA. 相似文献
990.
Chien-Chung Tsai Hsiang-Chun Wei Jheng-Syong Wu Chien Chou 《Optics Communications》2008,281(11):3036-3041
In order to characterize the linear birefringence parameters (LBPs) of a multi-order wave plate (MWP) including ordinary refractive index no, extraordinary refractive index ne and the order number precisely, phase retardation measurement by means of large oblique incidence angle on the MWP has been proposed and demonstrated. However, the effects of spatial shifting and multiple reflections by the MWP depress the accuracy of the measurements significantly. Thus, we propose a retro-reflected geometry in a polarized heterodyne interferometer that can determine the LBPs of a MWP precisely. This method is not only able to reduce the spatial shifting effect but also avoids multiple reflections of the emerging beams. Experimentally, the oblique incidence angle in a range from 30° to 44° was scanned and the highest sensitivity ever for measurements of no and ne for an uncoated MWP was obtained. The detection sensitivity for the refractive indices (no,ne, no−ne) of an uncoated MWP can be up to 10−6. 相似文献