Optical properties of the atmosphere have important effects on the atmospheric radiation balance and on the functions of various advanced opto-electric instruments working in the atmospheric environments.Optical properties of the atmosphere including sky background radiation and surface reflectance are basic physical quantities for atmospheric radiative transfer, light propagation research, and can also find important application in remote sensing, adaptive optics, free-space optical communication, etc. The atmospheric environments of China are very complicated and popular models like US standard atmosphere can not be applied simply. We suggest to divide the whole territory into several typical regions according to the environment, the surface, the solar irradiance, and the climate condition. Systematic and long-term measurements on the optical properties of the atmosphere should be performed, and application models should be built on the statistical characteristics. Algorithm codes and softwares should be built in consideration of the atmospheric models.

The meteorologic parameters and atmospheric optical turbulence of three representative regions,southeast coast, Hefei zone, and northwest desert in China were measured. The typical characteristics of three measurement sites were analyzed on terrain and climate. The effects of different grounds on atmospheric surface layer turbulence were discussed. The estimating methods of atmospheric surface layer and free atmospheric turbulence were presented, and the optical turbulence forecast model was also considered. Bulk method has capability to estimate both over land and over sea. Comparison of C(2,n) measured and modeled and modeled can give consistent results after adjusting initial input data. The meteorologic parameters can estimate C(2,n) profiles.The free atmospheric optical turbulence of Hefei can be fitted by Hufnagel model.

Optical properties of aerosol in the regions of Hefei and southeast coast were systematically measured and statistically analyzed. Moreover, the characteristic models were established, and the statistical laws of the parameters such as size distribution, total number concentration, scattering coefficient, absorption coefficient and visibility, were obtained. These typical results are helpful to realize other kinds of characteristic optical parameters, as well as continental and maritime aerosol.

Statistical characteristics of cloud cover as functions of hours, months and seasons, the probability of cloud-free line-of-sight(PCFLOS) as functions of hours and elevations in Hefei and southeast coastal areas of China were obtained by using Total Sky Imager 880. In Hefei, year-averaged cloud cover is more at noon,less in the morning and at dusk. The cloud cover distribution in southeast coastal areas are contrary to those in Hefei. In Hefei, the cloud cover in spring or summer is usually larger than that in autumn or winter.Month-averaged cloud cover in Hefei is 50%～80%, while 40%～55% in southeast coastal area. Maximum season-averaged PCFLOS in Hefei is less than 0.35, while month-averaged PCFLOS in southeast coastal area is up to 0.7.

Atmospheric optical properties and object spectrum are the basic information to support remote sensing research. For the requirements of application, the optical characteristic database of atmosphere and object is developed. Information about the database system is introduced, such as developing background, the software structure, the main functions, message content and the desired applications.

A moderate resolution combined atmospheric radiative transfer(CART) software is developed and introduced. A brief introduction to the software is made. The main functions of the software, some case studies, and the applications are shown.

On the basis of the existing researches and the highly effective computational language FORTRAN 95, a practical computer program for simulating laser propagating in the atmosphere was developed. The program, based on the optical field's Maxwell equation and the multiple phase screen method, could numerically simulate the turbulence effects, thermal blooming and their mutual effects for laser atmospheric propagation.Four types of propagation paths and ten kinds of optical turbulence profiles are also included into the program,which make it possible to simulate the propagating process and the atmospheric effects for laser beam With a circular or rectangular aperture under currently available conditions. Moreover, the beam propagating process can be visualized simultaneously by utilizing open graphics library(OpenGL). With the friendly user interface and convenient parameter settings, the program can be widely used for predicting and evaluating the propagation effects in the fields of free space laser communications, lidar detecting and beam propagation investigation in random media.

Reliable simulation of optical remote sensing image owns strong application background. The development of optical remote sensing imaging simulation code(ORSIS) is described briefly. ORSIS consists of three simulation modules, simulation of ground sight optical characteristic, simulation of atmospheric radiative transfer and simulation of sensor. It can realize end-to-end simulation of multiplicate sensor. In addition, the application of ORSIS is introduced here.

Experimental research on laser propagating along an atmospheric path of 0.5 km, 1.0 km and 3.0 km was carried out in a marine surface layer. The characteristics of optical intensity fluctuation, beam wandering and atmospheric extinction were analyzed by a series of laser propagation tests at the visible (0.473 μm,0.532 μm and 0.671 μm) and mid-IR(3.8 μm) wavelength. Besides, the spectral analysis of optical intensity fluctuation reveals that the unique property dependent on the wavelength exists for laser propagation in the marine atmosphere.

The radiance measured in atmosphere is affected by the atmosphere. In order to obtain the original radiance of a taxget, the atmospheric transmission correction should be performed. The basic theory for atmospheric correction in the measurement of infrared radiance of target is introduced. Some methods for obtaining atmospheric transmittance are given, and the accuracy of atmospheric correction in infrared measurement is discussed.

Based on the limb-scan technique, the spectrum and vertical-distribution characteristics of radiation in the mid-infrared band(2～5 μm) are examined by using the popular sophisticated moderate radiative transfer model MODTRAN 4, especially aiming at simulating the limb radiance profiles for different solar/detector locations and other atmospheric/meteorological environments. Analysis indicates good and meaningful results.

With the development of imaging spectrum remote sensing technology, a better sharing and processing pattern need to be designed to meet the requirement for applying and processing imaging spectrum data. On the other hand, the development of computer network and distributed computing technology provides the basic condition for realizing the idea. A system architecture designed for distributed sharing and processing imaging spectrum data is provided.

Based on the analysis of the principle of spatially modulation of imaging Fourier transform hyperspectrometer, the simulation algorithm in each step was studied in the process of acquiring data by the energy transmission, and the energy transmission model of imaging Fourier transform hyperspectrometer was established. Computer simulating of the energy transmission model was carried out. The simulation interferogram is consistent with the practical interferogram, and the simulation model is proved well.

It is very difficult to observe the celestial bodies in the daytime. The methods of spectro-polarimetric imaging and the skylight polarization measurements in real-time are adopted to largely reduce influence of atmospheric scattering. The SNR and contrast of celestial bodies detection in the skylight background are enhanced. The principle of spectro-polarimetric imaging for the celestial bodies detection in the severely atmospheric scattering was discussed. The related experimental system was introduced. The experimental measurements of spectro-polarimetric imaging for the stars were performed. The 6.33m star can be measured using spectro-polarimetric imaging in the daytime. This result of experiments was compared with that of spectral imaging. The results indicate that the contrast of celestial bodies detection using spectro-polarimetric imaging is enhanced obviously. Hence, it shows that the technique of spectro-polarimetric imaging can be applied to the research of celestial bodies observation in the daytime.

An atmospheric correction algorithm of satellite image for turbid water of coastal areas is put forward using synchronous measuring MODIS data. Supposed that the atmospheric condition above the turbid water and the coastal areas is identical in a certain space range, this algorithm is to use the atmospheric properties retrieved by the turbid water coastal areas based on MODIS water pixel to make atmospheric correction by using the 6S radiation transfer model and taking account of the adjacency effect. Atmospheric correction was applied to QuickBird-2 imagery and CBERS-02 imagery for turbid water of coastal areas. The atmospheric correction results and the analysis of retrieval errors were given. The experiment proves that atmospheric correction of satellite imagery for turbid water coastal areas using MODIS data is efficient and adaptive without need of ground data.