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1.
邓玉强  孙青  于靖 《物理学报》2011,60(2):28102-028102
提出了一种测量群延迟的新方法,利用白光干涉仪产生的光谱干涉,通过时间频率联合分析直接得出群延迟,减小了传统相位差分方法产生的误差,并通过测量结果减去系统背景,进一步提高了光学元件色散测量的准确度. 该方法适合于具有复杂色散光学元件群延迟和色散的准确测量,也适合于慢光器件群速度延迟的测量. 关键词: 色散测量 白光干涉 时间频率分析 超快激光  相似文献   

2.
时间位相调制对高强度三次谐波转换的影响   总被引:4,自引:4,他引:0  
在惯性约束聚变研究中,为了利用光谱色散进行光束匀滑以及抑制KDP晶体等大口径光学元件中的横向受激布里渊散射,通常需要对激光脉冲进行时间位相调制.详细讨论了高功率条件下KDP晶体Ⅰ/Ⅱ角度失谐三倍频方案中,时间位相调制对三次谐波转换效率和脉冲频谱的影响.研究结果表明,时间位相调制会导致三次谐波转换效率明显下降.  相似文献   

3.
共孔径元件是强激光发射光学系统极为重要的光学部件。本文研究了隐埋光栅型共孔径分光元件产生色散的机理,提出补偿色散的方法,并给出色散补偿设计实例。  相似文献   

4.
以衍射光学元件相位延迟表达式为理论基础,采用光学材料的折射率柯西色散近似公式,研究并得到了多层衍射光学元件的相位延迟与材料的关系,以及衍射效率与设计波长的关系.在400~700 nm可见光波段,以聚甲基丙烯酸酯和聚碳酸酯为基底材料,由柯西色散近似公式设计的多层衍射光学元件的最大带宽积分平均衍射效率为99.62%,相应的...  相似文献   

5.
宁悦文  胡摇  陶鑫  郝群 《应用光学》2021,42(4):698-702
光学元件轴向间距测量对精密光学系统的定位和装调具有重要意义。针对现有色散共焦测量系统中色散物镜结构复杂、色散范围小的问题,提出基于偏振衍射色散共焦的光学元件轴向间距测量方法,将传统折射共焦镜头几百毫米的轴向尺寸和复杂的装调需求简化为数毫米的单片镜,简化了系统结构。透镜间距和厚度测量实验表明,间距测量误差为10 μm。  相似文献   

6.
增益介质的色散对锁模激光器输出脉宽和啁啾的影响   总被引:2,自引:2,他引:0  
孔勇  陆雨田  王宁 《光子学报》2003,32(9):1035-1037
利用时间域内各光学元件的传播矩阵,在考虑了增益介质的色散后,对锁模激光器输出的脉宽和啁啾做了理论方面的推导,并做了相关的数值模拟,结果表明:当不考虑增益介质的色散时,其输出脉宽啁啾值为零;而考虑了增益介质的色散后,啁啾值随色散值的增加先增加而后降低,且存在一个最大值,脉宽随色散值的增加而增加.  相似文献   

7.
二元光学超光谱成像仪分光系统设计   总被引:3,自引:0,他引:3  
二元光学元件用作透镜在原理上色差非常大,若不在设计上做出补偿,则会限制其在宽波段上使用。阐述了利用二元光学元件色散特性的新型超光谱成像仪的基本原理和应用前景。由于国内加工衍射透镜工艺条件的限制,提出利用折衍混合透镜代替衍射透镜来实现色散和成像,介绍了此透镜系统的设计方法,利用光学设计软件进行分析和评估,希望对二元光学超光谱成像仪的设计具有指导意义。  相似文献   

8.
刘永智  沈革 《光学学报》1994,14(5):34-538
报道一种用光学色散元件进行光学鉴频的新方法。在干涉滤光片构成的实验系统上证实了最初的理论设想。  相似文献   

9.
剩余三阶色散对相位共轭偏振孤子的影响及其补偿   总被引:1,自引:0,他引:1  
陈伟成  徐文成  罗爱平 《光子学报》2007,36(6):1061-1064
光学相位共轭中剩余三阶色散不利于共轭孤子的稳定传输,导致孤子脉冲具有更大的时间抖动.本文提出在传输线末采用具有正三阶色散的色散位移光纤补偿光学相位共轭中的剩余正三阶色散.数值结果证明了其可行性.同时也分析其补偿的物理机制.  相似文献   

10.
双光栅快速扫描光学延迟线的色散补偿   总被引:1,自引:0,他引:1  
李栋  丁志华  孟婕 《光学学报》2007,27(3):505-509
光学相干层析成像(OCT)系统的纵向分辨力不仅与光源的带宽有关,而且与系统中两干涉臂间的色散匹配有关。如果色散没有得到精确匹配,将使光学相干层析成像系统的纵向分辨力达不到所预期的理论值。色散问题在超高分辨光学相干层析成像系统中尤为突出。提出了一种基于双光栅快速扫描光学延迟线(RSOD),用于光学相干层析成像系统的色散补偿。该方法中新增的光栅引入了光栅间距这一独立变量,其与常规单光栅快速扫描光学延迟线机构中的光栅离焦量一起,可使光学相干层析成像系统中的群速度色散(GVD)和三阶色散(TOD)同时得到补偿。分析了双光栅快速扫描光学延迟线的色散特性和色散调节原则,并提供了一个典型光学相干层析成像系统中的色散补偿实例。  相似文献   

11.
肖燕  郭淑琴  李仲豪  周国生 《光学学报》2001,21(9):025-1030
用短法研究含三阶色散的非线性薛定谔方程,讨论了厄米-高斯光脉冲在三阶色散介质中的传输特性,给出了近似解析解,并且同计算机数值模拟传输结果进行了比较,结果表明近似解有助于在理论上研究短脉冲在色散介质中的传输。  相似文献   

12.
We demonstrate that it is possible to perform a fractional Fourier transform of an incident pulse with a continuously variable degree of fractionality, using a dispersive and nonlinear Kerr medium. This medium acts as a linear waveguide for the optical pulse if its intensity is small and if the refractive index is nonlinearly time-dependently modified by a simultaneously launched bright soliton. For optical pulses the dispersive and nonlinear medium is perfectly equivalent to a graded-index refractive medium for optical beams.  相似文献   

13.
The chirped structure of the white-light continuum generation (WLCG) pulse produced by focusing 800nm laser pulse with a pulse duration of 150fs (FWHM: full-width-at-half-maximum) onto a 2.4 mm thick sapphire plate was investigated by the optical Kerr gate technique with normal hexane as the optical Kerr gate medium. The observed WLCG was positively chirped, the measured anti-Stokes spectrum of WLCG ranges from 449 to 580nm with a temporal span of 2.56ps. When using metal reflecting mirrors to eliminate the group velocity dispersion (GVD) effect, we found that a span of 1.3ps still remained, indicating that the chirped pulse cannot be accounted for simply by GVD of the pulse propagation in the dispersive media. Our results suggest that the light-induced refractive index change due to the third-order nonlinear optical effect leads to an additional positive group velocity dispersion, which contributes to an important portion of the observed temporal broadening of the chirped WLCG. In addition to using reflective optical elements instead of dispersive optical elements, an effective way of reducing the chirp is to minimize the optical path length of the WLCG medium.  相似文献   

14.
By introducing an intracavity Doppler shift in a resonator with a highly dispersive nonlinear medium, a train of optical pulses is generated whose features are related to the slow/fast-light response of the medium. The cavity transmission is asymmetric and the pulse shape is modified differently depending on the direction of the Doppler shift, hence, on the sign of the group delay provided by the dispersive process.  相似文献   

15.
The transformation of the envelope of a Gaussian pulse incident on and reflecting from a nonlinear dispersive medium is studied. It is shown that the pulse envelope transforms considerably upon reflection near the optical resonance frequency and the nonlinearity of the medium may appreciably distort the reflected pulse. Away from the resonance frequency, conditions may arise when the shift of the reflected pulse does not lead to the loss of the Gaussian form. In this case, the influence of nonlinearity is insignificant.  相似文献   

16.
Optics and Spectroscopy - A theory of optical two-component pulse of self-induced transparency in a dispersive medium has been developed. Using the generalized version of the perturbative expansion...  相似文献   

17.
Frequency-resolved optical gating is used to characterize the propagation of intense femtosecond pulses in a nonlinear, dispersive medium. The combined effects of diffraction, normal dispersion, and cubic nonlinearity lead to pulse splitting. The role of the phase of the input pulse is studied. The results are compared with the predictions of a three-dimensional nonlinear Schr?dinger equation.  相似文献   

18.
A theory of compression of short optical pulses with quadratic phase modulation in a dispersive medium has been developed. The results of numerical simulation of the equation for the light wave field are reported. The conditions are found at which a pulse is compressed to one oscillation period. The optimal phase modulation index providing the maximum pulse compression is estimated.  相似文献   

19.
《Comptes Rendus Physique》2009,10(10):1008-1013
A novel technique to produce large all-optically controlled tunable delays of 100 ps pulse train in optical fibers is demonstrated. The configuration of the delay line basically consists of two main stages: the wavelength conversion via semiconductor optical amplifiers and the group velocity delaying via a dispersive optical medium. The wavelength-converted signal was precisely delayed over a wide temporal range from picoseconds to nanoseconds using a dispersive fiber, preserving the wavelength and the bandwidth of the signal. 100 ps FWHM signal pulses were delayed continuously up to 14 ns with moderate pulse distortion, corresponding to a 140-bit delay. To cite this article: L. Thévenaz, S. Chin, C. R. Physique 10 (2009).  相似文献   

20.
An ultra-short pulse propagating in a resonant dense atomic medium experiences an important distortion due to a strong modification of its spectral phase. This distortion cannot be corrected using the usual simple dispersive devices (a pair of prisms, gratings, etc.). We present here an experimental demonstration of the compensation of this effect using a dual 640-pixel high-resolution pulse-shaper device. A cross-correlation intensity measurement combined with the XFROG (cross-correlated frequency-resolved optical gating) spectral phase measurement of the compensated pulse are performed; efficient correction of the resonant dispersive phase is shown. A spectacular temporal compression of the propagating pulse is then obtained. PACS 92.60.Ta; 42.50.Md; 42.65.Re; 42.79.-e  相似文献   

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