摘要:

A sensitive differential light detector is described which consists of two antiparallel silicon photovoltaic diodes and a current‐to‐voltage converter. The device is optimized to the detection of small differences in intensity. The noise and signal transfer features are considered, and an application example is given.

ISSN:0034-6748    

DOI:10.1063/1.1135804

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

The current paper describes a simple construction which allows the monitoring of the radial dependence of the extracted and mass identified ion currents in a hollow cathode stationary afterglow apparatus at any time during the afterglow. The main feature of the monitoring device is a fully bakeable and moveable vacuum seal between polished stainless steel and polished Al2O3ceramic.

ISSN:0034-6748    

DOI:10.1063/1.1135805

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

Electrical resistance measurements at 4.2 K on simple screw‐fastened joints between two pieces of bare copper, between two pieces of gold‐plated copper, and between two pieces of silver indicate the potential usefulness of such joints for thermal contact down to millikelvin temperatures.

ISSN:0034-6748    

DOI:10.1063/1.1135782

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

We demonstrate that a microwave power source to operate electrodeless discharge lamps can be built by modifying an inexpensive microwave oven at about 1/3 the cost of a commercial unit.

ISSN:0034-6748    

DOI:10.1063/1.1135806

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

A thermostatic control for a tungsten incadescent lamp is described. The circuit employs an operational amplifier feedback circuit to adjust the filament current and thereby achieve a constant filament temperature. The filament temperature is adjustable over a wide range by adjusting a potentimeter. Since the calibration of the thermostat does not, in principle, require temperature or radiometric measurements, the design may be useful in setting up a primary radiometric standard.

ISSN:0034-6748    

DOI:10.1063/1.1135807

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

A kinematic mirror mount that offers simple fabrication without compromising range or rigidity is described.

ISSN:0034-6748    

DOI:10.1063/1.1135808

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

A double frequency operation of the recently introduced grazing angle dye laser is demonstrated. By using two mirrors to reflect different order of diffraction the laser oscillates at two different frequencies, independently tunable over the entire gain profile of the dye.

ISSN:0034-6748    

DOI:10.1063/1.1135809

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

A small fixed point device is designed to be permanently mounted on a dilution refrigerator. The device contains Be and In samples with transitions at about 25 mK and 3.4 K.

ISSN:0034-6748    

DOI:10.1063/1.1135783

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

A simple and inexpensive method to excite compressive ion acoustic waves with relative amplitudes &dgr;n/n≲0.45 is described.

ISSN:0034-6748    

DOI:10.1063/1.1135810

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

A simple mirror holder which permits the use of locally damaged laser morrors by allowing the undamaged areas of the reflector to be aligned along the laser optic axis is described. The mirror holder has an eccentric step for housing the mirror and a concentric aperture through which the undamaged surface of the reflector is utilised. By varying the eccentricity and by rotating the mirror inside the step the entire surface area of the reflector can be used successively.

ISSN:0034-6748    

DOI:10.1063/1.1135780

出版商:AIP    

年代:1979

数据来源: AIP