摘要:
The invention relates a alkali-free aluminoborosilicate glasses having the following composition (in % by weight, based on oxide): SiO2 50-70, B2O3 0.5-15, Al2O3 10-25, MgO 0-10, CaO 0-12, SrO 0-12, BaO 0-15, with MgO+CaO+SrO+BaO 8-26, ZnO 0-10, ZrO2 0-5, TiO2 0-5, SnO2 0-2, MoO3 0.05-2. The glasses are particularly suitable as substract glasses for display and photovoltaic applications.
摘要翻译:本发明涉及具有以下组成(以重量%计,基于氧化物)的无碱铝硼硅酸盐玻璃:SiO 2 50-70,B 2 O 3 0.5-15,Al 2 O 3 10-25,MgO 0-10,CaO 0-12,SrO 0-12,BaO 0-15,MgO + CaO + SrO + BaO 8-26,ZnO 0-10,ZrO 2 0-5,TiO 2 0-5,SnO 2 0-2,MoO 3 0.05-2。 眼镜特别适用于显示器和光伏应用的减光眼镜。
摘要:
A receiver is disclosed for receiving coded optical a signals in an optical asynchronous communications system using a CDMA method based on periodic spectrum encoding. It has a first optical detector unit (PD1) and a second optical detector unit (PD2) which are preceded by a first periodic optical filter (Rx1) and a second periodic optical filter (Rx2), respectively. The roundtrip time of the second filter (Rx2) is shifted by approximately one quarter of the lightwave period of the received signal with respect to the roundtrip time of the first filter (Rx1). The inputs of the filters (Rx1, Rx2) are connected to the communications system through an optical splitter (KOP). The amplitudes of the outputs of the two filters are squared by means of two squarers (Q1, Q2) and added by means of an adder (AD). This makes the receiver (R) less sensitive to any drift of the filter transfer function.
摘要:
A receiver (R) is disclosed for receiving coded optical signals in an asynchronous optical transmission system using a CDMA method based on periodic spectrum encoding. The receiver (R) has a filter device (Rx) for decoding received signals as well as an optical detector unit (PD). The filter device (Rx) consists of a periodic filter (PRx) and a prefilter (VOR) whose transfer function causes the cosine transform of the optical frequency spectrum of the signal to be limited to a predeterminable range of a tuning curve. This reduces crosstalk between adjacent channels in the tuning range, and increases the maximum permissible number of transmitters.
摘要:
3-Pyrroline-2-carboxylic acid derivatives of the formula I ##STR1## are prepared by eliminating the sulfonic acid residue, with the aid of a base, from a compound of the formula II ##STR2##
摘要:
Compounds of the formula ##STR1## where A, B, D, R.sup.1 and R.sup.2 have the meanings stated in the description, are described. The compounds are suitable for controlling diseases.The novel compounds are prepared via compounds of the formulaH.sub.2 N--CH.sub.2 --G--M
摘要:
A coupling for mounting and positioning photographic, motion picture and video accessories and the like. A receiving base couples the positioning head to an equipment stand shaft, the receiving base being rotatable about the axis of the stand shaft. A first terminus of the receiving base incorporates an axially oriented beveled surface which is disposed within a cylindrical bore disposed through the head housing. The receiving base is maintained within the cylindrical bore in the housing through the engagement of and the force imposed thereon by an impinging stud bearing upon the beveled surface. A support post is mounted within the cylindrical bore of the housing extending outwardly in opposition to the receiving base. The end of the support shaft extending from the housing is fully rotatable about its interface with the housing. The engagement of the impinging stud against the beveled surface of the receiving base places the adjacent ends of the receiving base and support shaft in frictional engagement permitting the support shaft to be secured in a desired position.
摘要:
An optical frequency-encoded CDMA transmission system is presented in which received optical signals are decoded in the electric part of an optical receiver (12). To that end, the optical receiver (12) has a single photodetector (6) which converts received light into an electric signal, and which is directly or indirectly connected to a decoding unit (9, 10; 13, 14, 15), for recovering the information contained in the characteristic frequency-encoded spectrum.
摘要:
A coupling for mounting and positioning photographic, motion picture and video accessories and the like. A mounting sleeve is adapted to be secured to an equipment supporting member. A fixed positioning disc depends from and is integral with the mounting sleeve. A cylindrical shaft is axially coupled to and extends from the fixed positioning disc. A first rotatable positioning disc is disposed about the cylindrical shaft, a frictional stabilizing member being disposed between the fixed positioning disc and the first rotatable positioning disc. A second rotatable positioning disc is annularly disposed about the cylindrical shaft in proximity to the first rotatable positioning disc. The adjacent surfaces of the first and second rotatable positioning discs have disposed therein reciprocally aligned pairs of linear channels of varying width and depth, each pair of linear channels being adapted to receive and secure equipment supporting shafts of differing cross section. A securing handle is coupled to the cylindrical shaft and is adapted to impose an axial force to engage the rotatable discs and thereby securely position each pair of aligned, linear channels at any position along a 360.degree. arc relative to the axis of the mounting sleeve.
摘要:
The pulse repetition frequency of an optical pulse generator built with a fiber laser (LAS) is synchronized to a fixed clock frequency (fc). The synchronization is accomplished via means (M) for changing the optical path length of the resonator (RES), which is controlled by a signal from a control device (RE). The criterion for the synchronization is the effective value of an interference signal superimposed on the signal light, which increases with increasing deviation of the pulse repetition frequency from the clock frequency. A portion of the output signal (A) of fiber laser (LAS) is optically/electrically converted by the control device (RE), and the effective value of the interference signal is determined by filtering and rectifying the electrical signal obtained in this manner. After subsequent amplification and regulation, the control signal for the means (M) to change the optical wavelength is obtained. The control signal is additionally modulated with a wobble signal, so that the pulse repetition frequency always varies around the optimum value and is synchronized in this way.
摘要:
A passively mode-locked fiber ring laser (LAS) is disclosed for generating optical pulses whose repetition frequency is settable. The mode-locked fiber ring laser (LAS) contains an erbium-doped fiber (ER), a ring resonator (RES), a pump-light source (PUMP), an optical modulator (MOD), and a feedback loop (RS). A portion of the signal light, which is produced by stimulated emission and is composed of a plurality of pulse repetition frequencies, is processed in the feedback loop (RS) into a drive signal which is coupled to the control input of the optical modulator (MOD). The feedback loop (RS) includes an adjustable filter which filters the desired pulse repetition frequency from the signal light. Thus, optical pulses of a given repetition frequency are developed in the ring resonator (RES) and at the output (OUT) of the passively mode-locked fiber ring laser (LAS).