Selector™ Diffuse Reflectance Accessory 1. Introduction Thank you for purchasing a Specac product. Infrared radiant light when reflected from a solid surface can be either diffuse, specular or both (total reflectance) in nature. Diffuse reflectance is based upon the collection of radiation that has been diffusely scattered from the sample.
If you are in doubt as to whether your particular build of Selector™ accessory may be suitable for use and installation into a specific spectrometer system, please contact Specac for advice. Selector™ Accessory (in Right to Left Beam Build Configuration)
Selector™ Diffuse Reflectance Accessory 2. Unpacking and Checklist On receipt of your Selector™ accessory please check that the following have been supplied: (The Selector™ accessory will be supplied in its own carry case.) 1 Selector™ optical unit assembly in left to right or right to left beam direction configuration.
User Manual 3. Safety in Use of the Selector Accessory There are no specific precautions to be taken when the optical unit assembly of the Selector™ accessory is being used on its own standard Selector™ baseplate and sampling cups or diabraze sample pads, other than those associated safety procedures you may need to adopt for a specific sample type.
Selector™ Diffuse Reflectance Accessory 4. Optical Layout/Installation of the Selector™ The Selector™ accessory is a beam direction dependent accessory whereby infrared light radiation passes from the source to the detector of a spectrometer through the sample compartment area from a left to right (L to R), or right to left (R to L) orientation, as viewed from the front or above the spectrometer.
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User Manual Fig 2. Top View of L to R Beam Selector™ Optical Unit Fig 2 shows a top view of an L to R Selector™ optical unit alone and Fig 3 shows the same L to R Selector™ optical unit but from the underside.
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Selector™ Diffuse Reflectance Accessory Fig 3. Underside View of L to R Selector™ Optical Unit At the sample surface (e.g. a powder sample contained in a sample cup) the incoming light from E1 (7) will be scattered and it is the diffusely reflected component of this scattered light that is collected by the output ellipsoid mirror E2 (8).
User Manual After the scattered light has been collected by the E2 (8) mirror, the light is focused towards a fixed mirror (9) on its sample mount which then deflects the light to a movable (for rotation and tilt) mirror (10) on its mount.
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Selector™ Diffuse Reflectance Accessory Accordingly, similar to an L to R Selector™, Fig 5 shows a top view of an R to L Selector™ optical unit alone and Fig 6 shows the same R to L Selector™ optical unit but from the underside. Fig 5.
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User Manual in a cup that is positioned on top of the sample post (3) – see Fig 4. (In Fig 5 the E1 mirror (7) has been indicated, but it is positioned underneath the top cover of the ellipsoid mirrors arm assembly (4) – see Fig 4.) It is easier to see E1 (7) from the underside view of Fig 6.
Selector™ Diffuse Reflectance Accessory Note: The “off axis” design for both E1 (7) and E2 (8) mirrors being forward and on the same side of the sampling surface area means that when a flat, horizontal sample surface cup is used, then only diffusely reflected light will be collected by the E2 (8) mirror.
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User Manual Attachment of the Selector™ Optical Unit (1) to the Baseplate (2) It can be seen by comparison of the build of Selector™ accessory that an R to L beam direction version is a reversed “mirror” image of an L to R beam direction version for positioning of the mirror components.
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Selector™ Diffuse Reflectance Accessory Gently tighten to secure the Selector™ optical unit (1) to the baseplate (2), but do not overtighten the fixing screw (11). The optical unit base underside should not actually touch the top of the middle pillar (14). Fig 7.
5. Alignment of the Selector™ Accessory The Selector™ diffuse reflectance accessory has been pre-aligned before leaving Specac and will only require minor adjustment to some of the parts to maximize the light beam throughput when the accessory is installed in your spectrometer.
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Selector™ Diffuse Reflectance Accessory Ground spectroscopic grade KBr or KCl powder is recommended for use as a reference material for alignment and background spectra. The powder can be placed into the 11mm diameter sample cup (19) that is mounted on the top of the sample holder post (3). (See Fig 9.) Tip: It is best to fill the sample cup away from the optical unit (1) and spectrometer in case of accidental sample spillage.
User Manual Taking the standard 11mm diameter sample cup, fill it with finely ground KBr or KCl powder. When filled, carefully flatten the top surface of the powder with a piece of glass or polished metal, so that is level with the top edge of the sample cup (19).
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Selector™ Diffuse Reflectance Accessory decreases the signal strength, then carefully move the “Tommy bar” in the opposite direction until the optimum signal throughput strength is obtained from this mirror adjustment. (The rotational movement is quite fine for a setting between an optimum value and loss of the signal.) Fig 10.
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User Manual When mirror (10) has been adjusted for rotation to give an optimum peak value, then the tilt adjustment of this mirror can be made to try and optimise the light throughput value further. (See Fig 11.- diagram shows a close up of the mirror parts with the ellipsoid mirrors arm assembly (4) in the up/open Sample Loading Position for clarity.) Fig 11.
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Selector™ Diffuse Reflectance Accessory Output Ellipsoid Mirror E2 (8) Adjustment When the final output mirror (10) has been adjusted for both rotation and tilt to obtain an optimum throughput, the signal throughput may be improved further by adjustment of the output ellipsoid mirror E2 (8). (See Fig 12.) Ellipsoid Ellipsoid...
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User Manual Note: Usually it will not be necessary to make any adjustment to the corner grub screw (31) to obtain an optimum throughput for the E2 (8) mirror angle position. Micrometer Screw (25) Adjustment After adjustment of the final output mirror (10) and the output ellipsoid mirror E2 (8), it may be possible to peak up the throughput energy to a maximum value by adjusting the height of the ellipsoid mirrors (7 and 8) for their focal point from the sample surface in a sample cup (19).
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Selector™ Diffuse Reflectance Accessory After following the sequence of adjustment of final output mirror (10), then ellipsoid E2 mirror (8) and finally ellipsoid focus by adjustment of the micrometer screw (25), an optimum throughput value of light can be obtained. Note: A typical energy throughput level with use of a KBr powder reference sample for an optimally aligned Selector™...
User Manual 6. Sample Analysis Solid powder or irregular surfaced type samples are analyzed within the Selector™ diffuse reflectance accessory in the following way, either by the sampling cups provided or by the “diabraze” abrasive sample pads fitted to their respective pad holders. Sample Cup Options The Selector™...
Selector™ Diffuse Reflectance Accessory level edge of the recess to the cup. (A blade or smooth edged piece of plastic or glass is run over the surface to make level.) Because the sample cup (19) is easily detachable from the sampling post (3), filling the cup with a sample and the surface preparation can be done preferentially and more controllably, remotely in a safe area away from the spectrometer to minimize any risk of spillage of the sample and...
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User Manual Diabraze Pad Is Affixed To This Surface Of Holder This Part Of Holder Is Fitted Into Sample Post (3) Fig 16. Diabraze Pad and Diabraze Pad Mount Holder The diabraze pad (21) is 12mm in diameter and consists of small diamond particles embedded in an adhesive backed cloth material as the actual sampling surface.
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Selector™ Diffuse Reflectance Accessory Tilted (Total Reflectance) Sample Cup (GS19917) There is one Tilted Cup (23) provided with the Selector™ accessory. (See Fig 17.) Sample Placed Here In Recess Locking Screw Fig 17. Tilted (Total Reflectance) Sample Cup The tilted cup (23) allows for the collection of “total reflectance” which is a combination of both diffusely and specularly reflected components of light.
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User Manual The sample surface recess is set over at an angle of 45° to the horizontal and as such when the cup (23) is correctly positioned on the sample post (3), light projected from the input ellipsoid E1 mirror (7) to a sample surface set at this angle will be reflected for both its diffuse and specular component to be collected by the output ellipsoid mirror E2 (8).
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Selector™ Diffuse Reflectance Accessory D) Lower the ellipsoid mirror arm assembly (4) to the down/closed operating position set by the micrometer screw (25) resting on its ball stop (26). E) Collect a spectrum for the reference material. F) When the reference spectrum has been collected lift up the ellipsoid mirror arm assembly (4) to gain access to the sample post (3) to remove the sample cup with reference material.
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User Manual K) Collect a spectrum for the reference diabraze pad. L) When the reference spectrum has been collected lift up the ellipsoid mirror arm assembly (4) to gain access to the sample post (3) to remove the reference diabraze pad (21) on its mount holder (22). For collection of a sample spectrum, repeat the steps G) to L), but replace the reference diabraze pad (21) on a mount holder (22) with a diabraze pad (21) that has had an appropriate sample transferred to its...
For the sample cups (19, 20 and 23) cleaning, for any sample, but particularly if a salt sample such as KBr or NaCl has been used, Specac recommends that the cups are washed first with cold water to dissolve any residual salt content and are then rinsed with methanol to remove any potential organic residues.
User Manual 8. Legend (Bubble Part Number) Summary for the Selector™ Accessory (1) Selector™ optical unit assembly. (2) Selector™ baseplate assembly. (3) Sample post (no cup in position). (4) Ellipsoid mirror arm assembly. (5) First input fixed mirror. (6) Second input fixed mirror. (7) Input ellipsoid mirror E1.
Selector™ Diffuse Reflectance Accessory 9. Spare Parts for the Selector™ P/N GS03600 Pestle and mortar. P/N GS03610 KBr powder (50g). P/N GS19915 4mm diameter micro cup. P/N GS19916 11mm diameter standard sample cup. P/N GS19917 Tilted cup for total reflectance. P/N GS19918 Abrasive sample holder mount (packet of 2).
User Manual 10. Selector™ Baseplate Installation Guide Installation of the Selector™ Baseplate into the Spectrometer The following are descriptions of how to fit the specific L to R or R to L Selector™ baseplate into your appropriate spectrometer system. In most cases it is best to fit the Selector™...
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Selector™ Diffuse Reflectance Accessory P/N 549-039 - Bomem M100 Series (110, 120) - Beam direction: Left to Right Remove the spectrometer cover and 3” x 2” sample mount to gain access to the sample compartment. Place the Selector™ baseplate into the sample compartment with the sample holder post (3) to the front of the compartment.
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User Manual Remove the spectrometer cover and 3” x 2” sample mount to gain access to the sample compartment. The Selector™ diffuse reflectance accessory may be fixed to its baseplate and the whole assembly is located directly onto the kinematic mount features of the spectrometer. Fit the L to R Selector™...
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Selector™ Diffuse Reflectance Accessory P/N 549-386 - Bruker Tensor 25, 37, Quicklock 33, Vertex 70, 80 Beam direction: Right to Left Remove any 3” x 2” mount plate used in the spectrometer from the spectrometer sample compartment. Place the Selector™ Quicklock baseplate into the sample compartment with the sample holder post (3) to the front of the compartment.
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User Manual Remove any 3” x 2” mount plate used in the spectrometer from the Bruker baseplate. Place the Selector™ baseplate into the sample compartment (on the Bruker baseplate) with the sample holder post (3) to the front. The two fixing screws of the Selector™ plate are passed through the slots of the Bruker plate and the two screws are turned anticlockwise to tighten the plates together.
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Selector™ Diffuse Reflectance Accessory P/N 549-042 - Mattson Galaxy Series 2000, 3000, 4000, 5000, 6000, 7000, Genesis Series, RS, Infinity - Beam direction: Right to Left Two sets of pillars are supplied with this baseplate. The set of shorter pillars are used for the Genesis Series spectrometers which have a lower beam height than the other instruments.
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User Manual Remove any 3” x 2” mount plate used in the spectrometer. Place the Selector™ baseplate into the sample compartment with the sample holder post (3) to the front of the compartment. Hold the baseplate in position using the two cap head 8-32UNC screws supplied. Fit the L to R Selector™...
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Selector™ Diffuse Reflectance Accessory P/N 549-031 - Nicolet 500, 700, 710, 740, 800, 5PC, 5SXC, Magna, Protege, Avatar, Nexus, 6700, iS10, iS50 - Beam direction: Right to Left Remove any 3” x 2” mount plate used in the spectrometer. Place the Selector™ baseplate into the sample compartment with the sample holder post (3) to the front of the compartment.
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User Manual Remove any 3” x 2” mount plate used in the spectrometer. Place the Selector™ baseplate into the sample compartment with the sample holder post (3) to the front of the compartment. The baseplate is held in position by two location pins into the front support rail of the spectrometer and by tightening of the pull down thumb nut (supplied) to the instruments own fixing screw that passes through the slot at the front of the baseplate.
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Selector™ Diffuse Reflectance Accessory P/N 549-086 - Perkin Elmer PE2000 , Spectrum2000, GX, Beam direction: Right to Left Remove any 3” x 2” mount plate used in the spectrometer. Place the Selector™ baseplate into the sample compartment with the sample holder post (3) to the front of the compartment.
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Hold the baseplate in position using the two cap head M5 screws supplied. Fit the R to L Selector™ optical unit (1) in accordance with the instructions on page 14. Any Other Spectrometers For advice concerning spectrometers not included in this manual please consult your nearest Specac representative.
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Systems Engineering Inc. -Tokyo Fax: 215 793 4011 Tel: 03 3946 4993 Fax: 03 3946 4983 United Kingdom email:systems-eng@systems-eng.co.jp Specac Ltd. - London Website: www.systems-eng.co.jp Unit 12, Science & Innovation Centre Halo Business Park Spain Orpington Teknokroma S.Coop C. Ltda...
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Brilliant Spectroscopy™ www.specac.com SPECAC INC. SPECAC LTD. 414 Commerce Drive Unit 12, Science & Innovation Centre Suite 175, Halo Business Park Fort Washington, Orpington PA 19034, USA Kent BR5 3FQ Tel: 215 793 4044 Tel: +44 (0) 1689 873134 Fax: 215 793 4011...
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