Computational ghost imaging has great application prospect in the fields of national defense and biomedical because of its features of breaking the diffraction limit, being able to image under extremely weak background and harsh conditions. However, susceptible to the noise of the space environment, it has a low environmental signal-to-noise ratio. This paper propose an algorithm of interpolation computational ghost imaging(ICGI) in the field of computational ghost imaging. For the purpose of weakening the influence of dynamic interference in the ghost imaging, it insert specific patterns to a digital micromirror device in the original light-emphasis sequence, linearly estimate the change in noise by illuminating incoherent light, and correlate the optical signal of the object with the optical signal of the incoherent modulated light to calculate and reconstruct the image of the object. And This algorithm and the quality of image is improved by means of interpolating between different amounts of random patterns and inserting specific patterns of different complexity.
We propose and demonstrate a new correlation imaging method using a periodic light source array. The image of the object is reconstructed by exploiting the correlation between the total intensity of the beam interacting with the object and the precomputed intensity distribution patterns of the light source. The implementation of this experiment is quite simple and low-cost without the need for a beam splitter or spatial light modulator. Due to its single-pixel detection configuration, it should have great potential in many imaging applications.
Proc. SPIE. 10033, Eighth International Conference on Digital Image Processing (ICDIP 2016)
KEYWORDS: Signal to noise ratio, Image compression, Digital image processing, Imaging systems, Sensors, Image processing, Computer simulations, Image analysis, Digital micromirror devices, Information theory
In this paper, an evaluation criterion based on image complexity is proposed in ghost imaging. According to the iterative performance of ghost imaging, characteristic factors of describing image complexity are introduced for seeking a new evaluation criterion to improve evaluation method. The proposed image complexity can be utilized to assess the iterative performance of different ghost imaging algorithms. The assessment results indicate that the proposed image complexity has a similar function with SNR, which is used to evaluate the iterative performance of ghost imaging. Compared with other existing evaluation methods, the obvious advantage is availability when the original image is unknown, and experiment results demonstrate that the new evaluation criterion is valid in ghost imaging.
Proc. SPIE. 9795, Selected Papers of the Photoelectronic Technology Committee Conferences held June–July 2015
KEYWORDS: Signal to noise ratio, Infrared sensors, Infrared imaging, Detection and tracking algorithms, Imaging systems, Sensors, Image retrieval, Digital micromirror devices, Spatial resolution, Signal detection
Traditional imaging are mostly based on the principle of lens imaging which is simple but the imaging result is heavily dependent on the quality of detector. It is usual to increase the detector array density or reduce the size of pixels to improve the imaging resolution, especially for infrared imaging. It will decrease the light flux causing the noise enhance relatively and add the cost on the contrary. Besides, there is a novel imaging technology called ghost imaging. We present a new infrared imaging method named computational ghost imaging only using a bucket detector without spatial resolution, which avoiding the allocation of flux on the pixel dimension as well as reducing the cost.
Rayleigh backscattering noise, which is one of the reasons that limit the sensitivity, has been deemed as noise in traditional resonant optic gyroscopes. However Rayleigh backscattering noise is one of the incentives of mode splitting phenomenon in high-Q resonators. Regarding the change of the resonance frequency of the resonator caused by the scattering signal as a measurement, we can use mode splitting to measure temperature, size of nanoparticle, etc. Light is confined by total internal reflection in whispering gallery mode (WGM) optical resonators, which is characterized by high-Q factors and small mode volumes. With regards to this, we propose a sensing mechanism based on mode splitting in high-Q WGM optical resonators. It is possible for us to measure the angular velocity of carrier according to the changes in the resonant frequencies of the two splitting modes. We propose the Miniature resonant optic gyroscope based on mode splitting (MROG-MS) with WGM resonators in the paper. Considering the Sagnac effect, mode splitting in high quality optical micro-resonators, and the rotation-induced impact on backscattering process, we modify the equations of motion that describe mode splitting, derive the explicit expression of angular rate versus the splitting amount, and verify the sensing mechanism by the simulation based on COMSOL. Furthermore, after monitoring the transmission spectra at different number of scattering particles, the simulation shows that mode splitting phenomenon resulted by single particle is more suitable for angular velocity measurement.
Previous research employed natural background fractal features to detect man-made target for imaging infrared terminal guidance missile. The method is some effective but the optical turbulence is overlooked, which will disturb natural background intrinsic fractal. When the missile flies in atmosphere, there exits turbulent flow over the IR windows which will degrade the optical wave-fronts. In this paper, a new method considering degraded wave-fronts features is proposed for man-made moving target detection in natural background. To pre-process the infrared image and obtain the area in which target may exit, the image is divided into blocks and each block fractal dimension is calculated and compared. Then optical flow of the block is calculated from successive images to determine the moving target. The method is more applicable to actual missile fly environment, simulation results show that it reduces the optical flow calculation complexity and can detect the target availably.