— Filter Modules — Long Pass Cut-On Filters — Slits — Tungsten Source Module — Stepping Motor Controller — Detector Modules — Detector Accessories — Fiber Optic Cable

FILTER MODULES

HIGHER ORDER BLOCKING FILTER ASSEMBLY
Required to block higher order (λ/2, λ/3, λ/4, etc.) radiation. Higher order blocking filters are Optometrics Long Pass Cut-On filters in an assembly which includes the monochromator slit. Plugs directly into the Mini-Chrom monochromator.

LONG PASS CUT-ON FILTERS
Long pass cut-on filters are used to prevent higher order radiation from the grating monochromator from entering the sample compartment. Optometrics' long pass cut-on filters are cored from selected color glasses which transmit radiation above and block radiation below a specified wavelength. The wavelength interval (transition interval) from blocking to maximum transmission is sharp, typically 25 to 35 nm.

Long pass cut-on filters are identified by a cut-on wavelength, i.e. the wavelength at 50% of maximum transmission. Long pass cut-on filters have an average high transmission of 85% from 15 to 20 nm above their cut-on wavelength to 2000 nm. Attenuation of radiation below the cut-on wavelength is due to absorption of the colorants in the glass and the thickness of the glass. Superior blocking in Optometrics filters (0.001%) is due to the use of 3 mm thick color glass.

Optometrics long pass cut-on filters are all epoxied in a black metal ring for easy mounting and handling and are 25.4 mm dia. x 9.65 mm thick. The cut-on wavelength is marked on all filters. Designed to mount directly in the Optometrics sample chamber (see page 10).

*Note that Mini-Chrom models 04 and 05 would require two filters to cover their entire wavelength range.

Specifications Cut-on Wavelength - ± 5 nm Blocking (Short wavelengths) - 0.001% Transmission (High z average) - 85% Transmission Range - Cut-on to 2000 nm Dimensions and Tolerances: Diameter (Mounted) - 25.4 mm ± 0.25 mm Thickness (Mounted) - 9.65 mm ± 0.15 mm Clear Aperture   20.0 mm ± 0.25 mm

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SLITS

CATALOG NO.	6-9001	6-9002	6-9003	6-9004	6-9005	6-9006
SLITSET DIMENSIONS	50 µ x 4 mm	100 µ x 4 mm	150 µ x 4 mm	300 µ x 4 mm	600 µ x 4 mm	1 mm x 4 mm
PRICE *	75.00	49.00	49.00	49.00	49.00	49.00

* Prices are in USD and are list prices only.

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TUNGSTEN SOURCE MODULE

The Tungsten Source Module includes a 20W tungsten halogen lamp in a quartz envelope, a lamp housing, shutter assembly and variable aperture assembly on a base plate and a regulated 12V DC power supply. Halogen compounds in the lamp recycle tungsten deposited on the inside of the envelope back to the filament. This cycling of tungsten prevents the gradual degradation of the lamp output, particularly in the ultraviolet and increases the life of the lamp. The module can be used as a visible and near infrared source (340 nm to 3 µ) or as a building block to construct a variety of spectrophotometric systems. The module has provisions for attaching a Mini-Chrom monochromator and/or an adapter plate. The addition of a Mini-Chrom converts the Tungsten Source Module to a compact and versatile monochromatic light source. A quartz lens in the lamp housing focuses radiation from the tungsten lamp onto the entrance slit of the Mini-Chrom, obviating the need for additional optics and time consuming alignment. With an adapter plate, the module can be easily attached to the Optometrics sample compartment. A silicon detector can then be added, resulting in a manual spectrophotometer or fluorometer. Overall dimensions in mm: 203 x 114 x 62; Weight 0.9 Kg (2.0 lbs).

Specifications Lamp Power Supply: Line regulation - 0.1% Load regulation - 1% Ripple - 1 mV RMS Max. Input Voltages - 105-126V AC, 60 Hz     210-252V AC, 50 Hz Output - 12V DC/ 2 A     (3 A start-up surge) Lamp: Type   Tungsten halogen in quartz envelope Power   20 W Color temperature   3200° K Nominal life   500 hours Spectral output   340 nm - 3 m Connector   G-4 plug-in

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STEPPING MOTOR CONTROLLER
The PCM-01 is a modular component, ideally suited for driving the Optometrics line of Scanning Digital Monochromators.

	Using a personal computer, the operator can move the monochromator to a specific wavelength and scan over a wavelength range.The PCM-01 application program can be used with Windows 95 or 98.  When a terminal is used to drive the monochromator, the user can access over 25 commands that control a variety of operations of the grating drive (e.g. including the distance to be moved, the initial and final velocities of the move, the acceleration, the time period for pauses, etc.). Commands can be sent at any time, even when the motor is operating. The motor controller board includes over 2,000 bytes of nonvolatile memory to store complex motion control programs.
Six different Scanning Digital Monochromators are available for use with the PCM-01. Each monochromator is fitted with a pair of entrance and exit slits specified by the user. Additional slits can be ordered separately.

SAMPLE COMPARTMENT
The versatile Optometrics Sample Compartment accepts standard 1 cm square cells or solid samples up to 50 x 50 x 10 mm. A quartz lens focuses incident radiation in the center of the cell or on the front surface of a solid sample depending on the position of the sample stage. Two additional quartz lenses focus transmitted, reflected or emitted radiation at the in-line or 90 degree detector ports. A filter holder, which accepts Optometrics' 25.4 mm diameter filters, is attached to the inside of each port.

When measuring the percent transmittance or absorbance of a solution or a transparent solid sample, the sample stage and detector are positioned in-line. Fluorescence or nephelometric measurements are made with the detector positioned 90 degrees to the incident radiation. Reflectance measurements from solid samples require rotating the sample stage 45 degrees and placing the detector 90 degrees to the incident radiation (see Optical Path Configuration drawing on page 11). Overall dimensions in mm: 218 x 168 x 92; Weight 2.5 Kg (5.4 lbs.)

(For information on detectors that plug into the sample compartment see pages 12-13. If monochromatic radiation is required, our Tungsten Source Module (page 9) and either a Digital or Scanning Digital Monochromator (pages 4-5) can be attached directly to the Sample Compartment.)

SPECULARREFLECTANCEACCESSORY
The specular reflectance accessory mounted in the sample compartment is designed to measure the reflectance of solid samples such as mirrors, paint samples, etc. The reflectance accessory is pre-mounted in the Optometrics sample compartment, which aligns directly to the exit port of an Optometrics Mini-Chrom monochromator. Monochromatic light from the exit slit of the monochromator is reflected onto the sample, which is held in position by a spring-loaded mount. The angle of incidence at the sample is 11 degrees. Light from the sample is reflected to the exit port of the sample compartment. A detector is placed at the exit port to measure the amount and hence the reflectance from the sample.

The standard sample compartment (this page) can be used for samples requiring 45 degree reflectance measurements whereas the Specular Reflectance Accessory is designed for measurements requiring an 11 degree angle of incidence. Maximum sample size is 7 x 14 cm.

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DETECTOR MODULES
Optometrics Silicon Detector Modules are designed for direct mounting on Mini-Chrom monochromators or in either aperture of the standard Sample Compartment. The modules are compact, low cost, simple to mount and require no user alignment. The silicon detectors have a wide spectral response (200 nm to 1100 nm) with a peak response at approximately 900 nm. The detectors cover the UV-VIS-NIR spectral region and are used extensively as components in analytical and biomedical instrumentation, and in research, teaching and quality control. In addition to their wide spectral response, photocells have excellent linearity and signal-to-noise ratios.

The Detector Module consists of a mounted silicon photodiode, an integral low noise, high speed and exceptionally high stability operational amplifier and a slit assembly in a rugged housing. Mounting is facilitated by a pair of banana plugs on the slit assembly. When exposed to electromagnetic radiation of sufficient energy, photocells generate an electrical signal. The signal is the result of a photon induced difference in potential between the P and N layers within the photocell, i.e. the photovoltaic effect. The signal is proportional to the energy of the impinging radiation and varies as a function of wavelength. The Silicon Detector Module incorporates a photocell with low dark current, a fast response time, a quartz window and thin P-layer for an enhanced response to ultraviolet radiation.

A slide switch enables the selection of the time constant and fast for the recording (RS) spectrophotometer and computer data acquisition. Power to the modules ( 15V DC) can be supplied with a wall mounted power supply (for 115V AC) or by an external power supply (for 230V AC).

Specifications  Detector Module with Silicon Photodiode Detector Type - UV enhanced Silicon Spectral Range - 200 nm to 1.1 m Peak Response - 950 nm 50 nm Photosensitive Area - 5.9 mm sq. Output Signal - 0 to 14V DC full scale "Slow" Time Constant - 50 mSec. Cut-off Frequency   3 Hz "Fast" Time Constant - 10 mSec. Cut-off Frequency - 15 KHz Radiant Sensitivity (A/W): - 0.1 @ 254 nm (Hg)   - 0.38 @ 632.8 nm (HeNe)   - 0.5 @ 930 nm (GaAs)

* Prices are in USD and are list prices only.

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FIBER OPTIC CABLE
The F. O. Cable plugs directly into the Mini-Chrom, functionally replacing the exit slit. It is supplied with a 600 micron slit assembly for use on the entrance side. The other end of the cable terminates in a conventional circular bundle. The cable is 152 cm (5 feet) long with a rectangular (4.0 x 0.6 mm) fiber array and slit adapter on one end and a 2.0 mm diameter bundle on the other. Non-standard cable configurations are available on request.

For applications below 400 nm, quartz fibers are available as special order items.

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