A compact directional backlight module of time-multiplexed auto-stereoscopic display based on side-glowing polymer optical fiber (SGPOF) is proposed. The optical system is mainly composed of SGPOF array and cylindrical lens array. Spatial crosstalk is reduced by inserting a grating film as multi-slit diaphragm between the SGPOF array and the cylindrical lens array. A theoretical model is constructed based on the imaging optics principle of the off-axis ray. In the experiments, the cylindrical lens array concentrates a small number of views on three different view zones, the display can provide high luminance. The measurement results show that the luminance uniformity of the backlight module is up to 89.6%, and in the viewing zone the crosstalk is lower than 10%. The backlight module is compacted that the thickness being only 7 mm. The full-resolution and low-crosstalk 3D images are realized by using SGPOF backlight.

设计了一种用于裸眼3D显示屏的低串扰新型双面柱透镜光栅板, 光栅板的入射面为等间距排列的与显示器子像素数量相同的凹形自由曲面光栅结构, 出射面为斜置的凸形自由曲面光栅结构.根据裸眼3D显示原理和几何光学原理推导了双面光栅板的光栅单元自由曲面设计公式和光栅参数计算公式.通过MATLAB编程计算和SolidWorks软件建模得到光栅板模型.用TracePro软件对所设计的光栅板模型进行光线追迹仿真, 结果表明: 参数优化后的6视点斜置柱透镜双面光栅3D显示在最佳视角的图像串扰度为0.068%, 与传统6视点斜置柱透镜光栅的最佳视角图像串扰度相比降低了2个数量级, 并且在观看距离2 000 mm~3 000 mm 范围内图像串扰度基本不变.

定向背光柱透镜光栅式多视点自由立体显示器的串扰和亮度均匀性问题是影响其广泛应用的主要因素之一.本文通过分析串扰产生的原因, 根据偏轴光线的成像光学原理, 推导出液晶显示屏光开关板列单元与柱透镜组成的偏轴光学系统的参数计算式.提出一种液晶显示屏光开关蝶形单元结构, 设计了采用该蝶形单元的定向背光自由立体显示背光源模组.模拟仿真结果表明：所设计的定向背光自由立体显示背光源可消除自由立体显示的串扰; 在视点平面90%观看区域的串扰度小于0.5%, 光束10%峰值宽度的串扰面积比γ=0, 光束90%峰值宽度比普通液晶单元结构的增大37%, 改善了不同位置观看图像亮度变化大的问题.

理论分析和实验研究了光源相干度对其产生的Bessel光最大无衍射距离的影响.以He-Ne激光器为光源, 用旋转毛玻璃法产生部分相干光, 经过扩束后再用轴棱锥法产生Bessel光束.通过移动旋转毛玻璃改变部分相干光的相干度, 测量其产生的Bessel光束的最大无衍射距离, 得到光源相干度与产生Bessel光束最大无衍射距离的关系.结果表明, 随着光源相干度的降低, Bessel光束最大无衍射距离明显变短, 当相干度g≈1下降为g=0.8时, 最大无衍射距离缩短了一半.用高斯-谢尔模型进行分析和模拟, 理论模拟结果与实验观察结果基本吻合.

An efficient LED projector is designed for the LED flat lamp without light guide plate (LGP), in order to get high-efficiency lighting capablility and low cost of LED flat lamp. By employing refraction and total reflection, uniform intensity distribution of the emergent light and high-efficiency lighting capablility are achieved. The simulation results show that the output efficiency and intensity distribution on LED flat lamp panel depend on the distance between projector and output panel, the rotation angle of the projector and the gap between projector and LED. It performs well in both lighting efficiency and uniformity, while a distance of 5 mm, a rotation angle of 2° and a gap of 1.2 mm are used with the panel size of 240 mm×360 mm in the LED flat lamp without LGP. And 96.6% of optical uniformity is achieved.

矩形光栅1级和0级衍射效率之比对光栅的凹槽深度敏感,介绍了将其应用于聚合物光栅生物传感器的原理和光栅衍射光信号检测电路系统原理。设计了锁相放大器的信号通道滤波器,获得带宽不大于1 kHz的窄带滤波特性;利用相敏检测器(PSD)结合二阶巴特沃思低通滤波器,使等效噪声带宽限制在20 Hz以内,避免了工频干扰,实验结果表明系统输出信噪比SNR可达4 000以上。

A plastic surface-relief grating as a wavelength division multiplexer is designed and fabricated with the conventional mould pressing technique using the transmission-type fused quartz phase grating as mask pattern and polycarbonate as basal material. The experiment results show that in an optimizing process, the plastic surface-relief grating has the highest firstorder diffraction efficiency under adequate groove depth and incident angle, and can be used as the best optical path for wavelength division multiplexing (WDM). We also establish the experiment setup for testing the WDM performance of the plastic surface-relief grating based wavelength division multiplexer. The results show that the proposed wavelength division multiplexer has the high-stability temperature characteristics, the low insertion loss of less than 5 dB, the large isolation of greater than 20 dB, the low polarization-dependent loss (PDL) of less than 0.4 dB and the relatively steep pass-band characteristics. It is a WDM device with good performance, which can be applied in short distance communication.

光镊利用强会聚激光对微粒产生的梯度力来捕获微粒, 可以进行无损、远程操控, 同时具有皮牛精度的测力特性, 已经成为物理学、生命科学和胶体化学等研究领域中不可缺少的研究工具。光镊效应可以表现微小的光子动量和角动量, 是物理学的重要教学工具。本文根据高斯光束传播和变换规律, 设计具有稳定捕获性能的最小化光镊, 并给出了典型参数。光镊系统由捕获激光、光束耦合系统、倒置生物显微镜和大数值孔径物镜组成, 成像系统由物镜、摄影目镜和CCD相机组成。本光镊系统具有紧凑特性, 同时通过保持物镜后瞳充满度来实现稳定捕获。在该最小光镊系统上, 可以根据用户需求增加光镊阱位操控系统、刚度调节系统和其他辅助设备以满足不同操控要求, 可以很好地满足科研和教学需求。

研究了可作为塑料光纤与石英光纤连接器件的锥形塑料光纤过渡器的制作方法及性能测试。采用重力垂直熔融拉锥法制作锥形塑料光纤过渡器,并研究其在实验室条件下的最佳工艺参数。重复实验发现,当加热电压为6.0 V,加热区中心温度在214 ℃附近,拉伸力为1.40 g左右时,塑料光纤的拉伸过程容易控制,拉伸后的塑料光纤表面具有良好的光学质量。测试显示锥形塑料光纤的透射率随着锥度的增大而减小,表面显微形貌良好,出射模式数明显减少,出射模模场强度集中在低阶模部分,可见光透射谱在400～500 nm的损耗加大。对测试结果的分析表明,采用重力垂直熔融拉锥法可以制备性能优良的锥形塑料光纤过渡器,实验得到的最佳工艺参数可为POF连接器、耦合器的实际生产提供参考。