Spectrophotometer with split beam optical system, customizable methods, and rechargeable battery
The iris portable spectrophotometer is unlike any of the products we have created in the past. It is different from our photometers as it allows for measurement in the spectrum of all wavelengths of visible light and not just pre–specified wavelengths. Spectrophotometers work by isolating light at specific wavelengths from white light. This compact meter incorporates a number of features that facilitate both fantastic performance and exceptional usability.
Advanced Split–beam Optical System
The optical system is the heart of a spectrophotometer. Ensuring the optical system is built with the best design and highest quality materials will guarantee accurate readings and a long life for the meter. When developing this meter our research and development team paid special attention to details and combined many small improvements to a typical spectrophotometer design to create a meter with unprecedented performance.
Replaceable tungsten–halogen lamp
To be able to measure in a wide variety of wavelengths a broadband light source is necessary. In the iris spectrophotometer this is accomplished by a tungsten–halogen lamp. As these lamps do not last indefinitely, it is necessary to change them throughout the life of the meter. The pre–alignment of the lighting fixture guarantees that the bulb is in the same position every time it is changed. This generates peace of mind as there is no need to worry about realigning the light source.
Beam splitter
The beam splitter is added to the optical system for use with a reference detector to ensure that the measurement compensates for any drift in the light source. It works by splitting the light emitted by the tungsten lamp into two beams and sending one beam of light to the reference detector that measures intensity. If there are any fluctuations in the light source the meter detects this and compensates through a mathematical calculation. The reference detector also saves battery life and leads to improved speed of the meter as the lamp doesn’t have to warm up prior to use.
Concave grating
This element of the optical system is what generates the spectrum of light. When the light from the tungsten lamp hits the grating it is met with interference coatings that turn the polychromatic white light into a rainbow. This rainbow contains dispersed light at all wavelengths in the visible spectrum. The rotation of this grating is what allows for a specific wavelength to be selected. This ability is one of the biggest differences between a spectrophotometer and a photometer. The concave grating which accomplishes this is superior to other types of diffraction, such as prisms, as it minimizes stray light generated and has constant bandwidth. It also combines elements of the optical system that would typically be separate, for example if a flat grating was used a concave mirror would need to be added in order to refocus the light. The combination of these two pieces creates greater efficiency and a smaller optical system to yield a more compact portable meter.
Narrow bandwidth and high resolution
Having a small bandwidth is necessary to accurately measure narrow peaks. The iris spectrophotometer maintains a narrow bandwidth of 5 nm resulting in good spectral resolution. This leads to accurate measurement of sharp, narrow absorbance peaks. Additionally, the high resolution of 1 nm generates greater sensitivity as the wavelength is closer to where the sample absorbs the most light.
System check
Upon turning on the meter a performance check occurs to confirm that the light source is working properly and to calibrate the position of the grating. The grating calibration works by scanning for the “zero order” light reflecting off the grating. If any mechanical problems are present, the meter will display an alert. This feature establishes confidence in measurements knowing that the meter is always working properly without needing to run any additional tests.
Low stray light
A common problem in spectrophotometers is stray light. Stray light can be light which is outside the wavelength the meter is measuring or also light at the proper wavelength but from outside the meter. This leads to inaccurate readings as this light would not be absorbed by the sample but would still be detected by the meter. This is a problem that is typically hard to control. Due to the design of the optical system we are able to keep this potential issue to a minimum to improve the linearity and accuracy of readings.
Universal Cuvette Holder and Auto–Recognition
The cuvette holder built into the meter holds both 22 mm round cuvettes and rectangular cuvettes with a 5 cm path length. Adapters for the cuvette holder are available to hold other 13 and 16 mm round cuvettes, and 10 mm square cuvettes. Rectangular cuvettes have longer path lengths which result in higher sensitivity in readings of low absorbance samples. Additionally, the meter permits the selection of the size of the cuvette used in custom user methods from the available sizes. For all methods, the programmed cuvette size is displayed on the screen to ensure the correct cuvette size is used, ensuring that the proper path length is being used by the meter when calculating measurements.
Built-in holder
Holds 22 mm round cuvettes and rectangular cuvettes with a 5 cm path length
Round adapter
Holds 13 mm round cuvettes
Square adapter
Holds 10 mm square cuvettes
Vial adapter
Holds 13 mm round vials
Usability Features
Customized methods
Step–By–Step Method Creation with up to 10 calibration points and flexible calculations for multi wavelength method.
Creating a customized method is easy and intuitive. The HI801 guides you step–by–step through the process of creating your own custom method. The intuitive user interface will guide you through naming your method, setting the measurement wavelengths, creating reaction timers, and calibrating the method. Up to 10 points can be used to calibrate methods.
Favorite methods
Always have your most frequently used methods readily available with the favorite methods feature. Directly from the home screen is access to user–programmed favorite methods, saving time.
Large high contrast custom LCD display
With a 6” display, the screen is large and easy to read. The high contrast makes every character on the display stand out even during outdoor use. The wide viewing angle allows for measurements to be seen from far away, so while working around the lab it is not necessary to hover over the meter to see the measurements.
Capacitive touchpad
Maneuvering the menus and using the meter is effortless with the capacitive touchpad. Featuring dedicated buttons specifically for setup, logging data, recalling data, and methods allows for quick and easy access to these functions. There is a key beep feature that can be enabled or disabled, for audible feedback that the key was pressed. Additionally, the meter also still recognizes key touches even through gloves.
General Features
When choosing a piece of equipment, making sure the product has all required features for the intended purposes is critical. When building the iris we included as many features as we could to aid in making this meter exceedingly versatile and convenient. From bare necessities such as long battery life and easy data logging and transfer, we have pushed the limits on seemingly basic features to make your life as easy as possible.
Spectral range
The meter features a spectral range of 340 nm to 900 nm allowing for a wide selection of analytical methods. The flexibility of this range permits compliance with many methods from regulatory organizations and associations for a variety of applications.
Pre–programmed methods
Programmed in the meter are more than 80 commonly used methods for chemical analysis. Methods can easily be updated by transferring the file from a computer to the meter or by a flash drive. Up to 150 factory methods can be saved in the meter and some chemical parameters have the option to switch between different chemical forms. Finding the product codes to order additional reagents is easy as the meter provides the appropriate reagent codes for each programmed method.
User methods
The ability to program up to 100 personal methods into the meter creates both versatility and customization. Methods can include up to 10 calibration points, 5 different wavelengths (which can be used simultaneously), and permits the use of 5 reaction timers. These features allow for many variations to be implemented into methods. Compared to a photometer there is no longer a limitation by factory methods. If a certain parameter is not offered or a modification to a pre–programmed method is required, the meter can be customized to suit your needs.
Battery operated
The meter features a rechargeable lithium ion battery that lasts for approximately 3,000 measurements. Lasting well over a day of use in the field there is no need to worry about the battery life while out working without a power supply. The meter can be quickly recharged with a dedicated fast charging adapter.
Data Logging and Transfer
Transferring data from a meter should always be simple and straightforward. Impressively the meter can store up to 9999 measurements in the memory. At any time data can be transferred to a PC or Mac as either a CSV or PDF file. No software is required, simply plug in a flash drive or plug it into a computer and export the data. The ability to save data as a PDF ensures higher integrity of the data as it cannot be easily changed. Additionally, a meter ID and a sample ID can be programmed to be saved along with logged measurements. With technical equipment wide–spread connection compatibility can often be an issue, which is why the iris features USB ports for both flash drive and a direct computer connection. Connectivity with a USB–A port to a flash drive can be used to transfer logged measurements from the meter and also to transfer method updates onto the meter. The USB–B port is used for a direct connection to a computer specifically for transferring logged data.
HI801-11 Holmium Filter
Validate iris Wavelength Accuracy
The HI801-11 is a holmium oxide glass filter that is used to validate the wavelength accuracy of the HI801 iris spectrophotometer. The filter is mounted in a 10 mm square anodized holder and comes with a protective plastic holder that protects the filter when not in use.
Glass filter mounted in anodized aluminum holder
Fits all spectrophotometers that can accommodate 10 mm square cuvette
Absorbance peaks measured at 361, 454, 536, and 638 nm
Holmium Oxide Filter
Supplied with certificate of analysis traceable to SRM2034
All values are certified and have an uncertainty of less than 0.1 nm
Packaged in a light-tight, plastic cuvette holder
About Holmium
Holmium is a rare earth element that is silvery white and malleable. Holmium reacts with oxygen to form holmium oxide. Glasses that contain holmium oxide or holmium oxide solution are useful in the calibration of spectrophotometers due to their sharp absorption peaks in the visible spectrum.
The National Institute of Technology (N.I.S.T.), formerly National Bureau of Standards (N.B.S.) uses a holmium oxide solution sealed into silica cuvettes as the standard reference material (SRM 2034) for traceability. The holmium oxide solution is prepared with holmium oxide dissolved in perchloric acid. This solution has many well-defined absorption bands. The SRM2034 was found to be stable for up to thirty years*
The HI801-11 is traceable to SRM2034 and is supplied with a certificate that identifies the peak absorbance values of the filter within 0.1 nm of uncertainty. The HI801-11 holmium oxide filter is used with the wavelength check mode found in the HI801 iris spectrophotometer. The filter is placed into the meter and the wavelength check mode is then used to verify the wavelength positioning. Once the check is complete the meter will display the wavelength peaks and they are compared to the values found on the certificate. The values should be within ±1.5 nm of the certified value.
* NIST Special Publication 260-192