• <tr id="yyy80"></tr>
  • <sup id="yyy80"></sup>
  • <tfoot id="yyy80"><noscript id="yyy80"></noscript></tfoot>
  • 99热精品在线国产_美女午夜性视频免费_国产精品国产高清国产av_av欧美777_自拍偷自拍亚洲精品老妇_亚洲熟女精品中文字幕_www日本黄色视频网_国产精品野战在线观看 ?

    Controlling the light wavefront through a scattering medium based on direct digital frequency synthesis technology*

    2021-01-21 02:11:00YuanYuan袁園MinYuanSun孫敏遠(yuǎn)YongBi畢勇WeiNanGao高偉男ShuoZhang張碩andWenPingZhang張文平
    Chinese Physics B 2021年1期
    關(guān)鍵詞:高偉

    Yuan Yuan(袁園), Min-Yuan Sun(孫敏遠(yuǎn)), Yong Bi(畢勇),?, Wei-Nan Gao(高偉男),Shuo Zhang(張碩),2, and Wen-Ping Zhang(張文平)

    1Center of Applied Laser,Technical Institute of Physics and Chemistry,Chinese Academy of Sciences,Beijing 100190,China

    2University of Chinese Academy of Sciences,Beijing 100190,China

    Keywords: optical transmission matrix, direct digital frequency synthesis technology, phase modulation,wavefront optimization

    1. Introduction

    Since the invention of the optical lens, the field of optics has not only had an impact on daily life but also in almost all areas of science and technology. With a conventional lens, typically made of transparent refractive materials, one can easily manipulate light with a large degree of freedom.However, it is difficult to control the optical near field after turbid media, where conventional optical components fail to access. The propagation of waves in the multiple-scattering regime is a very fundamental problem of physics with numerous applications ranging from solid-state physics and optics,to acoustics and electromagnetism.[1]

    A deeper approach to the study of complex media lies in the transmission matrix (TM) retrieval. This matrix is a subpart of the usual scattering matrix as defined in Ref. [2] for instance. The knowledge of the TM brings more fundamental insight into the medium. One can for instance extract from the TM the single and the multiple-scattering components,[3]the backscattering cone,and the field–field correlations.[4]Experimentally,the TM can encapsulate the experimental imperfections induced by optical misalignment,surface curvature,lens aberrations, and non-uniform laser illumination. Measuring the TM of a turbid medium has shown potential in focusing,delivering images, controlling transmitted energy, subwavelength imaging,[5–18]and customizing speckle statistics.[19–21]Especially, the optimized wavefront of an illumination beam calibrated by the TM method generates a focus through random scattering media.If this technology is utilized in the laser TV, the light efficiency from the diffuser into the optical engine will be largely improved.

    In the literature of measuring the TM, iterative approaches, like successive displays of Hadamard patterns or canonical patterns on a spatial light modulation (SLM), are usually adopted. The frequency-based focus optimization technique is one of the methods using canonical patterns,where each SLM phase element is modulated at a unique angular frequency and all the phase elements go through a 2π phase variation. By this method, different high-quality foci are obtained through a scattering medium. However, how to precisely generate successive phase patterns on a SLM with predefined frequency (i.e., the process of phase modulation)to fit the characteristics of the SLM device has not been illustrated in detail. An effective phase modulation technology is important for obtaining a correct result. As known, the SLM is an 8-bit digital device, and the gray values have a range from 0 to 255. The minimum increment of the phase both in each pixel and in adjacent pixels is 1 graylevel. Different from Hadamard patterns and four phases method,[5,22,23]the frequency-based focus optimization technique makes the increment of each phase element be decimals, varying with the frequency on each SLM element, and the phase values increase with an iterative process. If these decimals are not properly truncated with non-fitting values cropped,the deviation will gradually accumulate with the iterative process and finally fail to obtain the correct result. To avoid cumbersome truncation rules for huge phase values in the experiment, we introduce the direct digital frequency synthesis (DDS) technology to modulate each SLM phase element.

    In this paper,we illustrate the principle of the DDS technology and its application in SLM phase modulation. Based on full-field interference and the DDS technology, we determine the required wavefront through a Fourier transform of the detected signal and obtain a high-quality focus of coherent light through a 2 mm thick 120 grit diffuser. We expect this wavefront shaping method alongside the DDS technology to reduce speckle and power consumption in laser TV or laser holographic display in our further study.

    2. Method

    2.1. Procedure to measure a transmission matrix

    where smis the complex amplitude of the optical field used as a reference in the mthoutput mode. The phase φnis modulated at an angular frequency ωnand goes through a 2π phase variation, resulting in Imvarying. When one phase pattern is loaded onto the SLM,then projected onto the scattering sample, the corresponding output of the sample is imaged by the CCD. When a series of output intensity Imat the target position is recorded and Fourier transformed, the third term in Eq. (2) can be decoupled from the others and the optimized phase pattern is determined. Then we address the optimized phase pattern onto the SLM,a clear focus can be obtained.

    We divide the procedure of measuring the TM into three steps. Assuming the SLM consists of a K×L array of pixels,the SLM pixels are divided into two groups, one group modulates the impinging wavefront (signal beam) with the DDS technology,while the other part remains fixed in order to provide controlled reference beams.

    In step 1, each SLM phase element corresponding to the signal beam is modulated at a unique frequency,ω1,ω2,ω3,...,ωn,...,ωN, resulting in each SLM phaseshifted by φ1,φ2,φ3,...,φn,...,φN. The SLM frame is successively updated and loaded onto the SLM constantly, and finally,4N speckle patterns are recorded by the CCD.The detected target signal is Fourier transformed,and the phase values at the corresponding frequencies are determined.In step 2,after the phase corresponding to the first group is determined,the other group is modulated while the first group is maintained at the newly determined phase values. In the same way,we obtain 4(K×L-N)speckle patterns by the CCD.The detected target signal is Fourier transformed,and the phase value at the corresponding frequencies in the second group is determined. In step 3, with the measured phase profile in the first two steps loaded onto the SLM, a bright round focus will be observed on the CCD at the target position.

    2.2. Direct digital frequency synthesis technology

    We exploit the DDS technology to modulate the SLM phase element.[24]The frequency obtained by DDS technology is expressed as

    where k ranges from 1 to L (L=4N). Different frequency control word Mnwill cause different phase increments of the SLM pixel(i.e.,having different modulation frequency fn). It should be noted that φnkis cropped into the range of[0, 255]before it is shown on the SLM. Figure 2 simulates the phase modulation result using the DDS technology.Figure 2(a)illustrates the phase modulation on the first pixel of 4N successive SLM patterns. Figure 2(b)shows the magnification of the first 10 periods. With the DDS technology,the SLM phase is accurately and fully modulated in the range of[0,255].

    Fig.1. The basic principle diagram of the DDS applicate to the SLM.

    Fig.2. Simulation of phase modulation with the DDS technology.

    3. Experimental setup and results

    3.1. Experimental setup

    In our experimental setup,illustrated in Fig.3,a linearly polarized monochromatic laser beam with a wavelength of λ =632.8 nm is expanded and uniformly illuminates a phaseonly reflective SLM(Holoeye Pluto-2). The modulated beam from the SLM goes through a 4-f system and is projected onto a surface of a diffuser via an objective lens(100×,NA=0.85,Nikon, Japan). A 2 mm thick 120 grit ground glass diffuser(Thorlabs, DG10-120) is used to randomly scatter the light before it reaches the focal plane. The diffusing surface faces the 0.45 NA objective lens. The light-transmitting through the diffuser is collected using an objective lens(20×,NA=0.45,Nikon,Japan)and then projected on a camera(Manta G201B).Experimentally, we record the speckle pattern well above the Nyquist limit per speckle grain along each axis.

    To avoid cross-talk between neighboring SLM pixels,20×20 pixels are grouped to form one macropixel. We use a square array of 30×30 macropixels in the central part of the phase modulating region of the SLM. We vary, with a z-axis translation base,the position of the first objective to obtain the highest intensity enhancement, with respect to the 0.45 NA objective kept at a fixed position. The calculated phase by Fourier transform of the detected signal on the CCD is feedback to the SLM by programming instructions. In addition,owing to imperfections in the pixels of the SLM,a correction pattern is superimposed onto the optimized wavefront to allow pixel shifting.

    Fig. 3. Schematic of the apparatus. BS: beam splitter; P: polarizer;L1–L4: lens;obj1,obj2: objective len.

    3.2. Results and discussion

    Firstly, some of the varying intensity values on the first CCD pixel are tracked in Fig. 4, which helps to identify the response of the SLM device. When the effective oscillating intensity is Fourier transformed, the optimum wavefront can be obtained. Figure 5(a) is the pattern that is transmitted when a plane wave is focused onto the sample, a 2 mm thick 120 grit ground glass diffuser. The light forms a typical random speckle pattern. Based on the optical setup and the algorithm described above, we measure the TM of the sample. The row and column of the conjugated TM are the output and input channels, which correspond to the pixel indexes of the CCD and SLM. Figure 5(b) shows the reshaped 2-D optimized phase map of the 4950throw of the conjugated TM,i.e., compensating for the random phase through the sample to focus the transmitted light at (50, 50) on CCD, as shown in Fig. 5(d). Subsequently, we retrieve the phase map from the 1920thand 7980throws of the conjugated TM. Then we measure a clear focus at (20, 20) and (80, 80) on the CCD plane, separately, in Figs.5(c)and 5(d). In fact, by adjusting the target optimal phase map used as feedback, it is possible to observe a bright round focus at any target position.

    Fig.4. Varying intensity on the first pixel recorded by the CCD.

    We estimate the experimental SNR defined by the ratio of the intensity at the focus to the mean intensity of the speckle outside. In Figs.5(c)–5(e),the result of focusing on the single spot shows SNR=51, 48, and 51. From a theoretical point of view, monochromatic phase conjugation focusing through a multiple-scattering medium has been studied in Ref. [22].The general formulation for the enhancement of the focus is SNR ≈Ngrains, the total number of “information grains”, or degrees of freedom. In our experiment, Ngrainsis the number of pixels characterized by modulation frequency in the central region of the SLM,i.e., Ngrains=450. Using the theoretical formalism developed in Refs. [5,24], the effective SNR,caused by the effect of the reference beam,can be written as

    where the dominating ratio γ is 50%,denoting that the fraction of the SLM used to be modulated. (1-γ)/γ is the effect of the reference beam which contributes as the noise at the focal spot. The experimental SNR of the focus in Figs.4(c)–4(e)is 28%, 27%, and 28% of SNRref. We attribute this difference to the inhomogeneous voltage-phase response function of the SLM pixels,phase digitization due to the 8-bit depth of SLM,and the intensity nonuniform.

    Fig.5. (a)Random speckle with a flat phase profile displayed on the SLM,(b-d) focus profile with the measured phase pattern displayed on SLM,(e)Fourier transform determined phase pattern.

    Figure 6 illustrates that the full width at half maximum(FWHM) of the focus at (50, 50) is ~10 pixels of the CCD,or 44 μm, no matter on the horizontal X-axis or the vertical Y-axis. We also demonstrate that the size of the focus is independent of the number of the SLM pixels in use. In addition,although the SNR is significantly high,the sidelobes appear beside the central peak.These results from an incomplete control of the light. The number of the SLM pixels used is much lower than the number of modes that propagate through a scattering media. The uncontrolled modes generate a speckled background.

    Fig.6. The FWHM of the focus at the center on the horizontal X-axis and the vertical Y-axis.

    4. Conclusion and perspectives

    To conclude,a DDS technology alongside a full-field interferometric method is demonstrated to have the excellent ability to focus the transmitted light through a 2 mm thick diffuser. It is the first time that the DDS technology is applied to modulating the SLM phase element,which skillfully modulates the SLM phase,minimizes the experimental error/noise,and finally makes the procedure of the TM simple time-saving and accurate. Using this algorithm, a relatively accurate TM is measured, resulting in the SNR of the focus nearly 50 and the FWHM about 44 μm. The total time for reconstructing the focus is 800 s. The results show that the proposed method has the potential in improving the light efficiency and compensation for the phase of speckle-noise on image or video in laser display and holographic display,where similar diffusers were inserted in Refs.[25,26]. In addition, this method can be applied in ghost imaging, customizing statistics of speckle, and biomedical adaptive optics.

    Acknowledgment

    The authors thank Jinhai Bai for valuable discussions and insightful suggestions.

    猜你喜歡
    高偉
    Runaway electron dynamics in Experimental Advanced Superconducting Tokamak helium plasmas
    Current sensor based on diamond nitrogen-vacancy color center
    Effect of a static pedestrian as an exit obstacle on evacuation
    High-fidelity resonant tunneling passage in three-waveguide system
    我是“隱形人”
    江蘇教育(2021年59期)2021-12-02 18:35:17
    我是“隱形人”
    Analysis of asymmetry of the Dα emission spectra under the Zeeman effect in boundary region for D–D experiment on EAST tokamak?
    運(yùn)動(dòng)達(dá)人傾情環(huán)保5 年撿40000 余個(gè)廢瓶子
    北廣人物(2020年46期)2020-12-11 07:09:40
    秋天的風(fēng)
    金山(2020年3期)2020-04-15 03:56:36
    爬山虎
    国产伦理片在线播放av一区| 国产欧美日韩精品亚洲av| 亚洲精品粉嫩美女一区| 日本av免费视频播放| 国产成人啪精品午夜网站| 大片免费播放器 马上看| 每晚都被弄得嗷嗷叫到高潮| 国产一卡二卡三卡精品| 国产色视频综合| 欧美一级毛片孕妇| 久久精品国产综合久久久| 国产无遮挡羞羞视频在线观看| 80岁老熟妇乱子伦牲交| 18在线观看网站| 午夜久久久在线观看| 老司机深夜福利视频在线观看| 国产一区二区三区视频了| 下体分泌物呈黄色| 捣出白浆h1v1| 午夜福利一区二区在线看| 久久精品aⅴ一区二区三区四区| 午夜福利欧美成人| 啦啦啦免费观看视频1| 午夜福利乱码中文字幕| 国产精品久久久人人做人人爽| 丝袜喷水一区| 在线观看一区二区三区激情| 精品国产一区二区三区四区第35| 久久亚洲精品不卡| 久久精品熟女亚洲av麻豆精品| 女人高潮潮喷娇喘18禁视频| 国产高清激情床上av| 日韩熟女老妇一区二区性免费视频| 亚洲色图 男人天堂 中文字幕| 成人影院久久| 精品国产超薄肉色丝袜足j| 国产精品国产av在线观看| 国产成人精品久久二区二区91| 桃花免费在线播放| 五月天丁香电影| tube8黄色片| 91成年电影在线观看| 成年人黄色毛片网站| 精品免费久久久久久久清纯 | 啪啪无遮挡十八禁网站| 亚洲人成77777在线视频| 人妻 亚洲 视频| 免费少妇av软件| 1024香蕉在线观看| 19禁男女啪啪无遮挡网站| 大陆偷拍与自拍| 亚洲国产精品一区二区三区在线| 精品福利永久在线观看| 亚洲人成电影观看| 欧美日韩视频精品一区| bbb黄色大片| 操美女的视频在线观看| 国产精品一区二区免费欧美| 亚洲专区中文字幕在线| 99国产综合亚洲精品| 亚洲国产av新网站| 一本综合久久免费| 亚洲精品久久成人aⅴ小说| 国产福利在线免费观看视频| 国产激情久久老熟女| 午夜激情av网站| 久久亚洲精品不卡| tocl精华| 一区二区三区国产精品乱码| 涩涩av久久男人的天堂| 男女下面插进去视频免费观看| 亚洲第一欧美日韩一区二区三区 | 18禁国产床啪视频网站| 亚洲熟女精品中文字幕| 一区二区三区国产精品乱码| tube8黄色片| 亚洲精品中文字幕一二三四区 | 久久久久久久大尺度免费视频| 国产不卡av网站在线观看| 黑丝袜美女国产一区| 满18在线观看网站| 亚洲黑人精品在线| 人人妻人人澡人人看| 国产99久久九九免费精品| 女人被躁到高潮嗷嗷叫费观| 俄罗斯特黄特色一大片| 老司机福利观看| 一边摸一边抽搐一进一出视频| 国产又色又爽无遮挡免费看| 国产精品偷伦视频观看了| av天堂久久9| 日本黄色视频三级网站网址 | 国产黄频视频在线观看| 国产免费视频播放在线视频| tube8黄色片| 久久99一区二区三区| 国产成人啪精品午夜网站| 亚洲专区国产一区二区| 国产精品免费一区二区三区在线 | 精品国产乱码久久久久久小说| 少妇猛男粗大的猛烈进出视频| 丝瓜视频免费看黄片| 天天添夜夜摸| 亚洲国产中文字幕在线视频| 不卡一级毛片| 亚洲人成77777在线视频| 最新在线观看一区二区三区| 国产精品熟女久久久久浪| 午夜福利欧美成人| 亚洲色图 男人天堂 中文字幕| 丁香六月欧美| 国产精品麻豆人妻色哟哟久久| 天天操日日干夜夜撸| 欧美中文综合在线视频| 黄色 视频免费看| 露出奶头的视频| 首页视频小说图片口味搜索| 9热在线视频观看99| 亚洲国产看品久久| 99国产极品粉嫩在线观看| 国产97色在线日韩免费| 国产精品亚洲av一区麻豆| 国产aⅴ精品一区二区三区波| 欧美乱码精品一区二区三区| 亚洲一区中文字幕在线| 妹子高潮喷水视频| 在线观看免费视频网站a站| 久久精品人人爽人人爽视色| 嫁个100分男人电影在线观看| 18禁裸乳无遮挡动漫免费视频| 久久青草综合色| 又紧又爽又黄一区二区| 波多野结衣av一区二区av| 捣出白浆h1v1| 男女边摸边吃奶| 成人国语在线视频| 啦啦啦视频在线资源免费观看| 丝袜在线中文字幕| 国产91精品成人一区二区三区 | 午夜免费鲁丝| 午夜福利视频在线观看免费| 亚洲人成电影观看| 国产亚洲精品一区二区www | 丝袜人妻中文字幕| 脱女人内裤的视频| 国产又色又爽无遮挡免费看| 欧美人与性动交α欧美精品济南到| 99精品在免费线老司机午夜| av欧美777| 欧美成狂野欧美在线观看| 亚洲中文日韩欧美视频| 波多野结衣av一区二区av| 亚洲国产欧美一区二区综合| 亚洲成人手机| 精品人妻在线不人妻| 亚洲天堂av无毛| 搡老熟女国产l中国老女人| 精品一品国产午夜福利视频| 久久久国产成人免费| 香蕉久久夜色| 天堂动漫精品| 欧美黄色淫秽网站| 国产一区二区三区视频了| 国产精品自产拍在线观看55亚洲 | 老熟妇乱子伦视频在线观看| 欧美黑人欧美精品刺激| 久久久久视频综合| 少妇粗大呻吟视频| 国产精品 国内视频| 日本av手机在线免费观看| 97在线人人人人妻| 国产成人影院久久av| 啦啦啦视频在线资源免费观看| 亚洲欧美色中文字幕在线| 国产黄色免费在线视频| 一本久久精品| 十八禁网站网址无遮挡| 久久午夜亚洲精品久久| 国产精品一区二区在线不卡| 亚洲欧美一区二区三区久久| 操出白浆在线播放| √禁漫天堂资源中文www| 97人妻天天添夜夜摸| 美女午夜性视频免费| 久久99一区二区三区| 午夜激情久久久久久久| 黄片播放在线免费| 水蜜桃什么品种好| av视频免费观看在线观看| 91成年电影在线观看| 无人区码免费观看不卡 | 精品卡一卡二卡四卡免费| 视频区欧美日本亚洲| 日韩三级视频一区二区三区| 亚洲熟女毛片儿| 欧美 亚洲 国产 日韩一| av一本久久久久| 啦啦啦在线免费观看视频4| 国产高清videossex| 高清在线国产一区| 亚洲人成电影免费在线| 中亚洲国语对白在线视频| 超色免费av| 国产精品成人在线| 精品一区二区三区四区五区乱码| 日本撒尿小便嘘嘘汇集6| 欧美大码av| 久久精品国产综合久久久| 超碰成人久久| 黄色视频在线播放观看不卡| 亚洲国产欧美日韩在线播放| 日本欧美视频一区| 大香蕉久久网| 国产福利在线免费观看视频| 大香蕉久久网| 亚洲av欧美aⅴ国产| 亚洲成国产人片在线观看| 黄色成人免费大全| 老司机影院毛片| 一级片'在线观看视频| 激情视频va一区二区三区| 美女高潮到喷水免费观看| 大码成人一级视频| 欧美日韩亚洲高清精品| 电影成人av| 黄片播放在线免费| 天天躁狠狠躁夜夜躁狠狠躁| 成人手机av| 色播在线永久视频| 巨乳人妻的诱惑在线观看| 一区二区三区精品91| 精品高清国产在线一区| 国产91精品成人一区二区三区 | 国产午夜精品久久久久久| 亚洲成国产人片在线观看| 麻豆成人av在线观看| 国产三级黄色录像| 2018国产大陆天天弄谢| 久久久久久久国产电影| 桃红色精品国产亚洲av| 激情在线观看视频在线高清 | 啪啪无遮挡十八禁网站| 精品卡一卡二卡四卡免费| 另类亚洲欧美激情| 99热网站在线观看| 久久婷婷成人综合色麻豆| 肉色欧美久久久久久久蜜桃| 日日爽夜夜爽网站| 国产欧美日韩一区二区三| 女警被强在线播放| 日韩一区二区三区影片| 狠狠狠狠99中文字幕| 久久人人爽av亚洲精品天堂| 在线观看免费视频网站a站| 无人区码免费观看不卡 | 亚洲熟女精品中文字幕| 777久久人妻少妇嫩草av网站| 亚洲精品国产精品久久久不卡| 亚洲综合色网址| 成人av一区二区三区在线看| 视频在线观看一区二区三区| 无限看片的www在线观看| 精品一品国产午夜福利视频| 极品人妻少妇av视频| 少妇 在线观看| 露出奶头的视频| 久久久久精品国产欧美久久久| 亚洲av成人不卡在线观看播放网| 超色免费av| 老司机亚洲免费影院| 日韩熟女老妇一区二区性免费视频| 国产成人啪精品午夜网站| 999久久久国产精品视频| 一级片免费观看大全| 丰满少妇做爰视频| 亚洲精品美女久久av网站| 亚洲第一欧美日韩一区二区三区 | 母亲3免费完整高清在线观看| 国产精品电影一区二区三区 | 久久精品91无色码中文字幕| 我要看黄色一级片免费的| 日本精品一区二区三区蜜桃| √禁漫天堂资源中文www| 老熟女久久久| 中文欧美无线码| 欧美国产精品va在线观看不卡| av有码第一页| 精品国内亚洲2022精品成人 | 高清视频免费观看一区二区| 国产精品 欧美亚洲| 新久久久久国产一级毛片| 波多野结衣一区麻豆| 9热在线视频观看99| 日韩熟女老妇一区二区性免费视频| 91大片在线观看| 亚洲国产毛片av蜜桃av| 一区二区av电影网| 丝袜在线中文字幕| 嫁个100分男人电影在线观看| 国产成+人综合+亚洲专区| 岛国毛片在线播放| 黄片播放在线免费| 国产伦理片在线播放av一区| 午夜成年电影在线免费观看| 午夜福利欧美成人| 777米奇影视久久| 91字幕亚洲| 欧美亚洲 丝袜 人妻 在线| 欧美性长视频在线观看| 精品国产一区二区三区久久久樱花| 青青草视频在线视频观看| 一区福利在线观看| 熟女少妇亚洲综合色aaa.| 亚洲伊人色综图| 香蕉国产在线看| 国产精品久久久久久精品电影小说| 成人亚洲精品一区在线观看| 在线观看免费高清a一片| a级片在线免费高清观看视频| 欧美一级毛片孕妇| 在线观看人妻少妇| aaaaa片日本免费| 午夜精品国产一区二区电影| 精品熟女少妇八av免费久了| 欧美亚洲日本最大视频资源| 亚洲熟女精品中文字幕| 国产一区二区三区视频了| 亚洲精品自拍成人| 精品福利观看| 大型av网站在线播放| 午夜91福利影院| 日本黄色日本黄色录像| 青青草视频在线视频观看| av欧美777| 久久久久国产一级毛片高清牌| 成人国产一区最新在线观看| 无人区码免费观看不卡 | 一本色道久久久久久精品综合| 亚洲国产成人一精品久久久| 亚洲熟女精品中文字幕| 黄色 视频免费看| 又大又爽又粗| 侵犯人妻中文字幕一二三四区| 日本a在线网址| 黑人操中国人逼视频| 久久久水蜜桃国产精品网| 国产aⅴ精品一区二区三区波| 久久狼人影院| 亚洲综合色网址| 国产成人系列免费观看| 久久精品国产99精品国产亚洲性色 | 99国产精品99久久久久| 日韩熟女老妇一区二区性免费视频| 久久青草综合色| 久久国产亚洲av麻豆专区| 午夜福利,免费看| 伦理电影免费视频| 91麻豆精品激情在线观看国产 | 久久这里只有精品19| 成人av一区二区三区在线看| 国产欧美日韩一区二区精品| 飞空精品影院首页| 黄色片一级片一级黄色片| 免费在线观看影片大全网站| 操出白浆在线播放| 好男人电影高清在线观看| 日本av免费视频播放| 麻豆乱淫一区二区| a级毛片在线看网站| 亚洲午夜精品一区,二区,三区| 最近最新中文字幕大全免费视频| 成年版毛片免费区| 国产三级黄色录像| 国产精品 欧美亚洲| 99九九在线精品视频| 最近最新中文字幕大全电影3 | 国产亚洲欧美在线一区二区| 一级毛片电影观看| 丝袜喷水一区| 国产精品成人在线| 91麻豆av在线| 亚洲伊人色综图| 欧美日韩福利视频一区二区| 亚洲五月色婷婷综合| 久久中文字幕人妻熟女| 黑人欧美特级aaaaaa片| videos熟女内射| 亚洲熟女精品中文字幕| 午夜两性在线视频| 欧美日韩中文字幕国产精品一区二区三区 | 老鸭窝网址在线观看| 亚洲欧美一区二区三区久久| 国产一区二区三区综合在线观看| 大片电影免费在线观看免费| 韩国精品一区二区三区| 香蕉国产在线看| 777久久人妻少妇嫩草av网站| 90打野战视频偷拍视频| 啦啦啦中文免费视频观看日本| 国产不卡一卡二| 久久这里只有精品19| 超碰97精品在线观看| 精品免费久久久久久久清纯 | 国产成人av激情在线播放| 精品亚洲成国产av| 日韩有码中文字幕| 成人特级黄色片久久久久久久 | 丰满人妻熟妇乱又伦精品不卡| 免费黄频网站在线观看国产| tocl精华| 老熟妇乱子伦视频在线观看| 久久人妻福利社区极品人妻图片| 一级毛片精品| 另类亚洲欧美激情| 成人国语在线视频| 天天躁夜夜躁狠狠躁躁| 国产成人影院久久av| 女人爽到高潮嗷嗷叫在线视频| 十八禁网站免费在线| 亚洲第一欧美日韩一区二区三区 | 考比视频在线观看| 免费观看a级毛片全部| 久久精品亚洲精品国产色婷小说| 91麻豆精品激情在线观看国产 | 黄片小视频在线播放| 久久久久国产一级毛片高清牌| 涩涩av久久男人的天堂| 日韩有码中文字幕| 九色亚洲精品在线播放| 少妇裸体淫交视频免费看高清 | 999精品在线视频| 国产免费福利视频在线观看| 国产1区2区3区精品| 亚洲视频免费观看视频| aaaaa片日本免费| 天堂俺去俺来也www色官网| 欧美在线一区亚洲| 丝袜美足系列| 欧美黄色片欧美黄色片| 法律面前人人平等表现在哪些方面| 免费看a级黄色片| 在线观看免费午夜福利视频| 国产亚洲av高清不卡| 男女下面插进去视频免费观看| 国产精品久久久久成人av| 亚洲人成77777在线视频| 一级毛片女人18水好多| 国产免费av片在线观看野外av| 老司机午夜十八禁免费视频| 精品乱码久久久久久99久播| 桃红色精品国产亚洲av| 成人永久免费在线观看视频 | 亚洲色图综合在线观看| 久久久欧美国产精品| 老司机午夜福利在线观看视频 | 久久精品人人爽人人爽视色| 亚洲情色 制服丝袜| 国产欧美日韩一区二区三| 久久久久视频综合| 欧美日韩精品网址| 狠狠狠狠99中文字幕| 免费一级毛片在线播放高清视频 | 免费看a级黄色片| 久久久久久久精品吃奶| 国产片内射在线| 极品少妇高潮喷水抽搐| 又大又爽又粗| 国产亚洲精品一区二区www | 狠狠婷婷综合久久久久久88av| 日日夜夜操网爽| 亚洲成av片中文字幕在线观看| 久久热在线av| 国产主播在线观看一区二区| 亚洲精品国产一区二区精华液| 国产亚洲精品第一综合不卡| 老司机午夜十八禁免费视频| 悠悠久久av| 亚洲人成电影免费在线| 天堂俺去俺来也www色官网| a级毛片在线看网站| 国产精品1区2区在线观看. | 在线天堂中文资源库| 一级毛片电影观看| 久久人妻福利社区极品人妻图片| 亚洲第一欧美日韩一区二区三区 | 一个人免费在线观看的高清视频| 看免费av毛片| 久久av网站| 国产日韩一区二区三区精品不卡| 无遮挡黄片免费观看| 久9热在线精品视频| 久久国产精品影院| 一夜夜www| 美国免费a级毛片| 性高湖久久久久久久久免费观看| 人人妻人人添人人爽欧美一区卜| 久热这里只有精品99| 精品欧美一区二区三区在线| 免费黄频网站在线观看国产| 成人国产av品久久久| 精品人妻在线不人妻| 亚洲欧洲日产国产| 啦啦啦免费观看视频1| 久久久久久亚洲精品国产蜜桃av| 精品亚洲成国产av| 亚洲精品乱久久久久久| 少妇精品久久久久久久| 女人精品久久久久毛片| 韩国精品一区二区三区| 极品人妻少妇av视频| 精品亚洲成a人片在线观看| 欧美黄色淫秽网站| 国产男靠女视频免费网站| 免费不卡黄色视频| 亚洲成人免费电影在线观看| 国产福利在线免费观看视频| 色综合婷婷激情| 一二三四社区在线视频社区8| 正在播放国产对白刺激| 日韩欧美三级三区| 多毛熟女@视频| 80岁老熟妇乱子伦牲交| 黑人猛操日本美女一级片| 1024香蕉在线观看| 青青草视频在线视频观看| 精品人妻熟女毛片av久久网站| 99精品在免费线老司机午夜| 中文字幕人妻丝袜一区二区| 久久99热这里只频精品6学生| 捣出白浆h1v1| 男女高潮啪啪啪动态图| 欧美变态另类bdsm刘玥| 男女高潮啪啪啪动态图| 热99久久久久精品小说推荐| 国产精品一区二区在线不卡| 欧美日韩亚洲高清精品| 亚洲男人天堂网一区| 国产一卡二卡三卡精品| 亚洲精品国产色婷婷电影| 亚洲精品久久成人aⅴ小说| 国产亚洲午夜精品一区二区久久| 久久精品aⅴ一区二区三区四区| 国产男女内射视频| 日韩精品免费视频一区二区三区| 黄色丝袜av网址大全| 美女高潮喷水抽搐中文字幕| 色视频在线一区二区三区| 黄色视频不卡| 国产99久久九九免费精品| 久久狼人影院| 精品乱码久久久久久99久播| 在线播放国产精品三级| 亚洲成人国产一区在线观看| 久久影院123| 亚洲精品久久成人aⅴ小说| 操出白浆在线播放| 亚洲av成人不卡在线观看播放网| e午夜精品久久久久久久| 精品亚洲成国产av| 久久久国产一区二区| 国产又色又爽无遮挡免费看| 高清在线国产一区| 他把我摸到了高潮在线观看 | 看免费av毛片| av有码第一页| 一区二区三区国产精品乱码| 天堂动漫精品| 久久青草综合色| 成人免费观看视频高清| 香蕉久久夜色| 在线看a的网站| 久久国产精品影院| 久9热在线精品视频| 不卡av一区二区三区| 狠狠婷婷综合久久久久久88av| 久久久久网色| 高清毛片免费观看视频网站 | 亚洲视频免费观看视频| 欧美久久黑人一区二区| 亚洲精品美女久久久久99蜜臀| 丁香六月欧美| 国产亚洲精品久久久久5区| 五月天丁香电影| 国产有黄有色有爽视频| 久久久久网色| 国产色视频综合| 国产欧美日韩一区二区三区在线| 成年人黄色毛片网站| 12—13女人毛片做爰片一| 欧美精品一区二区免费开放| 亚洲熟女毛片儿| 99香蕉大伊视频| 亚洲三区欧美一区| 久久精品亚洲av国产电影网| 精品一区二区三区视频在线观看免费 | 国产在线免费精品| 9191精品国产免费久久| 精品国产乱码久久久久久男人| 女人爽到高潮嗷嗷叫在线视频| 黄频高清免费视频| 国产精品熟女久久久久浪| 母亲3免费完整高清在线观看| 精品少妇一区二区三区视频日本电影| 日韩大码丰满熟妇| 动漫黄色视频在线观看| 一进一出抽搐动态| 在线观看66精品国产| 欧美精品一区二区免费开放| 亚洲全国av大片| 精品久久蜜臀av无| 亚洲精品久久成人aⅴ小说| 我的亚洲天堂| 国产av精品麻豆| 亚洲欧洲精品一区二区精品久久久| 老司机亚洲免费影院|