The paper presents a method with the technique of combination filtering of spectrum and the technique of DSP control for the simulation and recognition of the spontaneously lightening object and stellar map in the universe. The magnitude and the spectrum of a star can be simulated in a wide dynamic range. We established the mathematical models of the Vega's visible light spectrum and luminous flux density. Tungsten-halogen lamp as a light source is used to fit the linear light of the spontaneously lightening object in the universe. Through the experiment, it shows that the more sub-channels there are while filtering spectrum in the visible spectrum, and the more degrees the variable neutral density filters and the narrow-band attenuators have, more close to the actual spectrum the simulated spectrum is. It is proved that using the PID technique is beneficial to the output of the accurate and steady radiation from the light sources. The experiment shows that the using of this method can get perfect result in fitting and simulating the spectrum, magnitude and the stellar map of the spontaneously lightening object . The analysis of the consistent result and the experimental error is also discussed in detail in this paper.
The Raman scattering of I<sub>2</sub> liquid-core optical fiber under the condition of resonance absorption in liquid-core optical
fiber is studied in this paper. Iodine is dissolved in transparent benzene to make solution of I<sub>2</sub> in benzene, and the
absorption coefficients of the solution are measured at certain wavelengths. The absorption curve can be divided into
non-resonance absorption region, pre-resonance absorption region, strict resonance absorption region, and
post-resonance absorption region respectively. Resonance absorption Raman scattering experiments are conducted by a
532 nm frequency-doubled Nd:YVO<sub>4</sub> laser, and the wavelength is in the strict resonance absorption region of solution of
I<sub>2</sub> in benzene. Compared with I<sub>2</sub>, the absorption of benzene can be neglected. Non-resonance Raman scattering of the
solution is performed using a 632.8 nm He-Ne laser, and no spectrum lines of I<sub>2</sub> are found. The study demonstrates that
there is one spectrum line of I<sub>2</sub> in the Raman scattering spectrum in the I<sub>2</sub> liquid-core optical fiber, but this line is not
found in the spectrum of the non-resonance and resonance absorption Raman scattering of I<sub>2</sub> solution in benzene using
absorption cell. The experiments proved that I<sub>2</sub> Raman scattering, is greatly enhanced by using both resonance
absorption and liquid-core optical fiber.