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Narrowband filters for precision monochromatic light sources
Vacuum~volume 39/number 10/pages 1009 to 1 020/1 989 Printed in Great Britain
0042-207X/8953.00+.00 Pergamon Press plc
V A C U U M News M a n u f a c t u r e r s and others Manufacturers and others are invited to submit information for inclusion in this feature. Items should be addrsssed to : Dr J S Colligon, Department of Electrical Engineering, University of Salford, Salford M5 4WT, UK
New products and developments N a r r o w b a n d filters for precision m o n o c h r o m a t i c light sources A range of dielectric narrowband interference filters is now available from Balzers. Purpose designed for the production of monochromatic light, they are suitable for use in a variety of analytical instruments such as colorimeters, sensitometers, polarimeters, flame photometers, refractometers and interferometers. Narrowband interference filters consist of a series of dielectric thin films vacuum deposited onto a suitable substrate. They operate on a complex process of constructive and destructive interference, which precisely selects a narrow range of wavelengths having maximum transmission efficiency. Other regions are either reflected or absorbed. Secondary maxima and unwanted wavelengths are suppressed by combining with s;uitable colour glasses that act as blockers. Typical performance characteristics for the filters are halfbandwidths of 0 nm, peak wavelengths tolerance of 4-2 rim, and a peak wavelength transmission that varies from 30 to 80%, according to the filter selected, within the 340-768 nm range. For the small quantity customer Balzers can provide a range of 30 standard wavelengths between 340 and 770 nm, applied to 10 mm diameter substrates. These are designed for operation at 0 ° angle of incidence, although others for use at 30 ° or 45 ° can be manufactured on request. Environmental limits include a temperature range of -40°C ~Eo+55°C and relative humidity not exceeding 60%. In the use of these filters very steep cut-on/cut-off slopes guarantee low interference from the transmission of unwanted wavelengths and the angle of these slopes can be determined from the relationship of the halfbandwidth with the tenth, hundredth and thousandth bandwith, i.e. the smaller the proportion the steeper the slope. The Balzers narrowband filters provide typical relationships of 1 : 1.6, 1 : 2.2 and 1 : 3.2, respectively. More information can be obtained from : Jim Rees Balzers High Vacuum Ltd Northbridge Road, Berkhamsted, Herts HP4 1 EN Tel 04427 862181 Telex 8209 VACUUM G Fax 04427 871727
The sensor tube and controller of the new l o w cost Pirani vacuum gauge system from the HPS Division of MKS Instruments.
temperature with pressure change, the response time is also much faster. Called the SensaVac Series 917 the system consists of a controller with an easy-to-read analogue display and a sensor tube which can be mounted in any position without changing reading. The gauge provides measurements from atmosphere to 10 -3 torr. All the controls are accessible from the front panel of the controller and standard features include two adjustable set points, single scale analogue output and operation on all common line voltages and frequencies. The SensaVac Series 917 system is very competitively priced. MKS instruments are marketed in the UK by Chell Instruments w h o provide a full technical advisory service. For further information please contact : Ron Mitchell Chell Instruments Ltd Tudor House, Grammar School Road, North Walsham, Norfolk NR28 9JH Tel 0692 402488 Telex 97198 Chell G Fax 0692 406177
N e w Pirani gauge f r o m M K S The HPS Division of MKS Instruments has introduced a new Pirani Vacuum Gauge system incorporating a rugged and corrosion resistant sensor tube with a unique temperature compensation method to improve accuracy. Because the sensor wire does not change
N e w M KS f l o w m e t e r calibration system MKS Instruments has introduced an advanced new microprocessor controlled flow calibration system for mass flowmeters and controllers. 1009
0042-207X/8953.00+.00 Pergamon Press plc
V A C U U M News M a n u f a c t u r e r s and others Manufacturers and others are invited to submit information for inclusion in this feature. Items should be addrsssed to : Dr J S Colligon, Department of Electrical Engineering, University of Salford, Salford M5 4WT, UK
New products and developments N a r r o w b a n d filters for precision m o n o c h r o m a t i c light sources A range of dielectric narrowband interference filters is now available from Balzers. Purpose designed for the production of monochromatic light, they are suitable for use in a variety of analytical instruments such as colorimeters, sensitometers, polarimeters, flame photometers, refractometers and interferometers. Narrowband interference filters consist of a series of dielectric thin films vacuum deposited onto a suitable substrate. They operate on a complex process of constructive and destructive interference, which precisely selects a narrow range of wavelengths having maximum transmission efficiency. Other regions are either reflected or absorbed. Secondary maxima and unwanted wavelengths are suppressed by combining with s;uitable colour glasses that act as blockers. Typical performance characteristics for the filters are halfbandwidths of 0 nm, peak wavelengths tolerance of 4-2 rim, and a peak wavelength transmission that varies from 30 to 80%, according to the filter selected, within the 340-768 nm range. For the small quantity customer Balzers can provide a range of 30 standard wavelengths between 340 and 770 nm, applied to 10 mm diameter substrates. These are designed for operation at 0 ° angle of incidence, although others for use at 30 ° or 45 ° can be manufactured on request. Environmental limits include a temperature range of -40°C ~Eo+55°C and relative humidity not exceeding 60%. In the use of these filters very steep cut-on/cut-off slopes guarantee low interference from the transmission of unwanted wavelengths and the angle of these slopes can be determined from the relationship of the halfbandwidth with the tenth, hundredth and thousandth bandwith, i.e. the smaller the proportion the steeper the slope. The Balzers narrowband filters provide typical relationships of 1 : 1.6, 1 : 2.2 and 1 : 3.2, respectively. More information can be obtained from : Jim Rees Balzers High Vacuum Ltd Northbridge Road, Berkhamsted, Herts HP4 1 EN Tel 04427 862181 Telex 8209 VACUUM G Fax 04427 871727
The sensor tube and controller of the new l o w cost Pirani vacuum gauge system from the HPS Division of MKS Instruments.
temperature with pressure change, the response time is also much faster. Called the SensaVac Series 917 the system consists of a controller with an easy-to-read analogue display and a sensor tube which can be mounted in any position without changing reading. The gauge provides measurements from atmosphere to 10 -3 torr. All the controls are accessible from the front panel of the controller and standard features include two adjustable set points, single scale analogue output and operation on all common line voltages and frequencies. The SensaVac Series 917 system is very competitively priced. MKS instruments are marketed in the UK by Chell Instruments w h o provide a full technical advisory service. For further information please contact : Ron Mitchell Chell Instruments Ltd Tudor House, Grammar School Road, North Walsham, Norfolk NR28 9JH Tel 0692 402488 Telex 97198 Chell G Fax 0692 406177
N e w Pirani gauge f r o m M K S The HPS Division of MKS Instruments has introduced a new Pirani Vacuum Gauge system incorporating a rugged and corrosion resistant sensor tube with a unique temperature compensation method to improve accuracy. Because the sensor wire does not change
N e w M KS f l o w m e t e r calibration system MKS Instruments has introduced an advanced new microprocessor controlled flow calibration system for mass flowmeters and controllers. 1009