双中心全息记录的矢量分析与记录方向优化

对描述双掺杂晶体非挥发性全息记录动力学过程的Kukhtarev方程进行了矢量分析,分析中考虑了体光生伏特效应和外加电场的作用。在小信号近似的基础上给出了双中心全息记录中记录与固定阶段空间电荷场的矢量解析解。在综合考虑空间电荷场的各向异性以及晶体有效电光系数的各向异性后,给出了双中心全息记录的优化记录方向。结果表明,对(Fe,Mn)∶LiNbO3晶体633nm寻常光记录,优化记录方向主要由有效电光系数决定,光栅波矢与光轴夹角为22°,方位角为30°;对(Fe,Mn)∶LiNbO3晶体633nm非寻常光记录,优化记录方向主要由固定空间电荷场决定,光栅波矢与光轴夹角为44°,方位角为90°。     

Heat Assisted Magnetic Recording with Matching Media and Recording Head Field

The dynamic performance of heat assisted magnetic recording （HAMR） on different media is investigated. Signal and signal-to-noise ratio enhancement are achieved in high coereivity perpendicular media with the aid of laser heating. Linear recording density is increased while saturation write current is lowered. Trailing field partial erasure is observed in lower coercivity media with a ring head, which causes signal reduction with increasing write current or application of a laser. Precautions should be taken against partial erasure in overall recording system optimization of HAMR in order to achieve ultrahigh recording density.     

Recording quantum gravitational effects

It is suggested that large-scale deep-water systems of DUMAND type should be used to record cosmic gravitons, gravitinos, and photinos at ultrahigh energies.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii Fizika, No. 10, pp. 79–82, October, 1982.     

Recording of ultrahigh-energy astrophysical neutrinos

This review is devoted to the problems of recording ultrahigh-energy neutrinos produced in distant astrophysical sources and during the decay of supermassive particles. Prospects for the detection of neutrino fluxes are considered based on peculiarities of the propagation and interaction of ultrahigh-energy neutrinos. The operating and planned facilities designed to investigate neutrinos from various sources are described: neutrino telescopes recording neutrino interactions in natural water and ice volumes; ground-based arrays of detectors and optical telescopes onboard orbital space stations capable of detecting neutrino-triggered horizontal air showers. Instruments based on new principles of recording neutrinos with extremely high energies are considered: radio telescopes designed to observe Cherenkov radio emission from neutrino cascades originating in such radio-transparent natural environments as the atmosphere, salt domes, ice packs, and lunar regolith; underwater acoustic detectors. It is shown that putting new facilities into operation will allow neutrinos from most of the known astrophysical sources with energies differing by more than ten orders of magnitude, from 10¹² to 10²²–10²⁴ eV, to be recorded.     

The Effect of Short-Wave UV Radiation in Recording Holographic Structures on Gelatin-Containing Recording Media (Overview)

The paper analyzes the SERS spectrum of hydroquinone adsorbed on nanoparticles of titanium dioxide (TiO₂). It is seen that the enhancement is stronger for a larger mean size of nanoparticles that is in agreement with an electrostatic approximation. In addition, it is found that there are the lines, which are forbidden in usual Raman spectra. There is also an enhancement caused both by the normal and tangential components of the electric field. This result is in agreement with the theory of SERS on semiconductor and dielectric substrates. The discovery of the forbidden lines indicates on the sufficiently large role of the strong quadrupole light-molecule interaction in such a system.     

酞菁铜薄膜的光记录特性

研究了有机染料酞菁铜（ＣｕＰｃ）真空蒸镀薄膜在可见及近红外区域的吸收光谱和光学常数，发现酞菁铜薄膜在５５０－７５０ｎｍ波长范围内具有较强的吸收，在静态测试仪上测试了酞菁铜薄膜的光存储记录特性，发现用低功率氦氖激光照样品时薄膜反射率变化较大，在酞菁记录层上覆盖金属反射层将提高写入激光的阈值能量并且增大反射率的对比度。     

Miniaturisation of High-NA Objectives for Optical Recording

High-NA objectives for optical recording have received a lot of attention due to the investigation of the Blu-ray Disc system. More recently to enable optical storage in portable devices, small building height optical drives have been studied requiring miniaturised high-NA objectives. Previously reported miniaturised objectives consist of two elements and are, therefore, less suited for mass production. In this paper the design and manufacturing of a miniaturised single element high-NA objective is reported. Furthermore, with the aid of non-periodic phase structures the tolerances of the objectives can be further expanded.     

Recording of spectral line shapes in time

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 53, No. 1, pp. 90–94, July, 1990.     

近距离数字全息术记录和再现问题

讨论了记录距离小于菲涅耳衍射要求的近距离数字全息记录和再现问题。对全息记录与再现中高次相位的补偿问题进行了分析,证明了在CCD的参量和记录距离给定后,只要记录时使物体的大小、球面参考光波的位置和距离满足一定的条件,即使在记录距离小于菲涅耳衍射要求的最小距离情况下,也可将高次相位的影响补偿到足够小,使得近距离数字全息的数字再现仍可用快速傅里叶变换算法计算。推导出了满足高次相位补偿的条件和满足补偿条件时的数值再现计算公式。实验结果与理论分析的结论相吻合,并给出了一种修正实际记录的参考光和计算机模拟的理想参考光之间偏差的方法。     

Recording of PIV images on photothermoplastic plates

In this paper we explore the possibility of utilizing commercially available photothermoplastic plates as recording support in Particle Image Velocimetry (PIV), to allow real time analysis of recorded data. An experimental apparatus has been developed which allows holographic recording and reconstruction of simulated PIV images. We show that double exposed photothermoplastic plates can successfully be analysed provided that a suitable recording/reconstruction scheme is used.     

Azodye Gelatin Films for Polarization Holographic Recording

Mordant pure yellow azodye in a matrix of gelatin is proposed as a medium for stable polarization recording. Relatively high values of birefringence are measured (over #x0394;n = 0.02). Polarization diffraction gratings are recorded with two circularly polarized waves and diffraction efficiency of 67#x0025; is achieved at 633 nm. Protected from the humidity, the recording is stable. Long-term radiation by a 633 nm probe beam is harmless as well. Unusual behaviour is observed when acting on the recorded grating alternatively with one of the recording beams. The left circularly polarized beam erases the grating sharply, while the right circularly polarized beam, before erasure, initially increases the diffraction efficiency.This paper was originally presented at the 2001 International Conference (2nd Joint OSJ-SPIE Conference) on Optical Engineering for Sensing and Nanotechnology, ICOSN 2001 which was held June 6-8, 2001 at the Pacifico-Yokohama Conference Center, Yokohama, Japan.     

Recording of one-dimensional holograms in MnBi films

A new system of holographic recording on moving MnBi film is described. The data to be stored are recorded in a track of non-overlapping 1-d Fourier holograms. A cavity-dumped argon laser is used for writing. The feasibility of this new system has been demonstrated by writing and erasing tracks consisting of 20 μm by 2 μm holograms. A maximum bit density of 10⁷ bit/cm² and a writing data rate of 10⁸ bit/s should be attainable with such a system.     

Recording and reconstruction of digital Gabor hologram

This paper looks at some as yet undisclosed observations in the recording and reconstruction of digital Gabor hologram. Small particles on the specimen plane diffract the illuminating spherical wave to form the object wave which interferes with the un-diffracted reference to form the in-line hologram. The interference is similar to that between two spherical wavefronts. It is shown that resolution enhancement can be achieved in the recording process through the use of wavefronts with different curvature. Numerical reconstruction of this hologram with a conjugate of the illuminating (reference) wave provides the in-focus real image at the object plane. It is exemplified that the proper choice of the reconstruction wavefront can optically magnify the reconstructed image enabling one to better visualize the resolution enhancement. Both theoretical analysis and experimental confirmation are provided for these observations.     

Information Approach to the Digital Recording of Signals

Radiophysics and Quantum Electronics - In this work, we study the problems of processing complex-nature signals subject to noise, which arise because of the insufficient dynamic range of these...