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为获得高性能紫外激光薄膜元件，急需研制紫外高反射吸收薄膜，实现吸收损耗的精确测量。本文采用离子束溅射技术，通过调控氧气流量实现了具有不同吸收的Ta2O5薄膜的制备。以Ta2O5薄膜作为高折射率材料，设计了355 nm的紫外高反射吸收薄膜。采用离子束溅射沉积技术，在熔融石英基底上制备了355 nm的吸收薄膜，对于A=5%的紫外吸收光谱，在355 nm的透射率、反射率和吸收率分别为0.1%，95.0%和4.9%；对于A=12%的紫外吸收光谱，在355 nm的透射率、反射率和吸收率分别为0.1%，87.4%和12.5%。实验结果表明，采用离子束溅射沉积技术，可以实现不同吸收率的355 nm高反射吸收薄膜的制备，对于基于光热偏转测量技术的紫外光学薄膜弱吸收测量仪的定标具有重要的意义。

Convolutional neural networks (CNNs) show state-of-the-art performance in tackling a variety of visual tasks. It is expected that a CNN can be applied to the 9-day hatching eggs classification. These hatching eggs are divided into fertile eggs and dead eggs. Because of the inter-class similarity and intra-class difference issues in 9-day hatching eggs datasets, the CNN classification method combining channel weighting (squeeze-and-excitation module) and joint supervision is proposed to improve the classification accuracy. We use the center loss and softmax loss together as a joint supervision signal. With such joint supervision, the CNN can obtain the deep features with inter-class dispersion and intra-class compactness, which enhances the discriminative and generalization powers. Simultaneously, channel weighting is adopted in feature extraction, which is added in each convolutional layer to make better use of the channel features. The experimental results demonstrate that the proposed method successfully solves the classification problem of hatching eggs. The accuracy of our method is 98.8%.

Bandpass filters are indispensable to the development of advanced optical and electro-optical systems used in space, defense, and terrestrial applications. In this paper, wideband deep cutoff bandpass filter of 750-900nm was designed and prepared by ion beam sputtering deposition technology. Long wave pass filter with high transmittance from 750 to 900nm and low transmittance from 400 to 730nm was designed and prepared on one side of the HB720 substrate. Short wave pass filter with high transmittance from 750 to 900nm and low transmittance from 930 to 1100nm was designed and prepared on the other side of the HB720 substrate. From the measured transmittance curve, the average transmittance was above 96% from 750nm to 900nm, the transmittance at the wavelength of 728nm and 928nm was less than 0.1%. The results indicated that high quality bandpass filter can be manufactured using the combination method of long-wave and short-wave filters.

The radiation wavelength of the carbon dioxide is 4.3μm. It is a kind of background noise that affect the image contrast in infrared imaging system seriously. Mirror is an important optical element in infrared optical system. This paper intends to design a 4.3μm wavelength filter base on the mirror. So, it is called reflective filter. It can replace the original mirror in the infrared optical system in order to filter out the radiation wavelength of the carbon dioxide and enhance the image quality. The reflective filter consists of metal and dielectric films. The absorption of the Al film which is the underlayer has been induced by the outer side dielectric multilayer films at 4.3μm. And it will keep high reflectivity in other wavelength at the same time. The design result as follow was obtained after optimization design. The average reflectivity is about 98% in the range of 3.7-4.2μm and 4.4-4.8μm (reflection bands) and the reflectivity is less than 10% at 4.3μm (absorption band) when the incident angle is 45°. The reflection phase of the metal-dielectric films was analyzed. The electric field distribution of reflection bands and absorption band was shown respectively. At last, in order to filter out the peak as much as possible, the design method and result of absorption band widening of the reflective filter was shown. Compare the all dielectric transmission minus filter, the layer number of the reflective filter is fewer and the total thickness of the coating is lower. Therefore, the manufacturing process became easier. The reliability became higher. More important, a better parameter of filter was obtained.