BTS256-PAR Light-Color-Spectral Meter

A State-of-the-Art PAR, Illuminance, Color Spectral Meter That Accurately Measures SSL as well as Traditional Light Sources

BTS256-PAR State-of-the-Art PAR, Illuminance, Color Spectral Meter
An Innovative New PAR & Lightmeter Designed Specifically For Solid State Lighting (SSL), CFL, Traditional Lamps & Displays

Features self-programming of up to five different end-user spectral weighting functions

It's Not Your Traditional PAR Meter
Fully Characterizes Any Type of Light Source for Precise Monitoring & Control in horticultural lighting in the lab, field or greenhouse.
Gigahertz-Optik's BTS256-PAR  Light-Color-Spectral Meter provides all necessary PAR Photosynthetically Active Radiation, illuminance (photopic & scotopic), color and spectral data to fully analyze SSL, CFL and any other type light source. Its Bi-Technology sensor improves measurement accuracy and is precisely cosine corrected.

Plant Growth Measurands:

  • PAR - µmol/(m²s)
  • DLI - Daily Light Integral (time resolved data logger)
  • R/FR - Red to Far Red ratio
  • Esy1, Esy2, Etp1, Etp2 weighting functions
  • Ech   
  • Emo/Pr       
  • Emo/Pfr      
  • Etp1  
  • Etp2  
  • 5 different self-programmable user spectral weighting functions  

Radiometric, Photometric, Colorimetric Measurands:

  • Ee (λ) spectral irradiance
  • Ev illuminance (fc & lux)
  • Es scotopic illuminance (fc & lux)
  • Ee irradiance
  • Es/Ev scotopic / photopic ratio
  • x; y CIE 1931 color coordiantes
  • u'; v' CIE 1976 color coordiantes
  • CCT correlated color temperature
  • Δuv deviation from the blackbody locus
  • X; Y; Z CIE color
  • Ra; R1..15 CRI - color rendering index
  • λdom dominant wavelength
  • pe purity
  • CIE 1931 color graphic with S-BTS256 software
  • CIE 1976 color graphic with S-BTS256 software
  • CRI Bar Plot with S-BTS256 software
  • λp peak wavelength
  • λc center wavelength
  • λs centroid wavelength
  • λ0,5 spectral half-width (FWHM)
  • TM-30-15 Rf fidelity index
  • TM-30-15 Rg gamut index
  • TM-30-15 Rf,h1..16 hue fidelity indices
  • TM-30-15 Rcs,h1..16 chroma change by hue indices with S-BTS256 software
  • TM-30-15 color vector graphic with S-BTS256 software
  • TM-30-15 Rf, Rg graphic with S-BTS256 software
  • Ez melanopic illuminance
  • Ee,z melanopic irradiance
  • Ev,mel melanopic daylight equivalent illuminance
  • Esc cyanopic illuminance
  • Ee,sc cyanopic irradiance
  • Emc chloropic illuminance
  • Ee,mc chloropic irradiance
  • Elc erythropic illuminance
  • Ee,lc erythropic irradiance

Customizable Display of Readings 
The BTS256-PAR´s high resolution display enables the user to choose between 11 standard measurement display configurations as well as five extra user customizable ones. Switching between the different displays is easy using the three front panel buttons. An additional Info-Display shows the measurement parameters currently under use.

Accurate Measurements with Bi-Technology Sensor 
The BTS256-PAR meter is equipped with Gigahertz-Optik´s BTS256 Bi-Technology light sensor which includes both a photometric photodiode and diode array. Any spectral mismatch error of the photopic sensor is compensated on-line using the diode array's measured spectral data. This reduces measurement uncertainty when evaluating any type of light source.

Photometrically Corrected Filtered Photodiode Light Detector 
The traditional light detector employing a silicon diode and a photometric correction filter still provides best dynamic range, linearity and response time. But it cannot perform color measurements and cannot actively adjust to the target light source's spectral function. This is why the Gigahertz Optik Bi-tech sensor is equipped with a second diode array detector that works with the filtered photodiode detector.

256 Pixel Diode Array Spectroradiometer 
The BTS256 light sensor´s CMOS diode array provides precise luminous spectral measurement data. The spectral data is used for luminous color value and scotopic illuminance calculations.

Automatic Dark Signal Adjustment 
On-line dark signal compensation dependent on the measurement time is accomplished by means of an electronic shutter located in front of the Bi-Tech Sensor enabling an optimum signal-to-noise ratio.

On-Line Complementary Use of Measured Data 
On-line measured data from each detector is used in a complementary method to enhance the overall measurement quality. The filtered photodiode‘s measurement values are used to improve the linearity of the diode array whereas the diode array‘s spectral data is used to correct for any spectral mismatch error of the filtered photodiode. This is essence of the Gigahertz-Optik Bi-Technology Sensor and what sets it apart from other light meters.

Modulated Light Measurement (PWM) 
Pulse width modulated (PWM) light characterized by short pulses and varying pulse intervals requires the device's measurement rate to be synchronized with the modulation frequency. The BTS256-PAR measures the light's modulation frequency with its fast filtered photodiode and the measurement rate is synchronized automatically.

Cosine Spatial Response
A basic requirement for accurate illuminance measurement is a precise cosine corrected measurement geometry (field-of-view).  This light detector spatial response allows light from different angles of incidence, such as in general and street lighting, to be angularly weighted correctly in the measurement. Despite its large 20mm large diameter the BTS256-PAR cosine correction corresponds to DIN 5036 Quality Class B with f2 ≤ 3%.

A Quality PAR / Luxmeter 
Through the cutting-edge Bi-Technology sensor concept, state-of-the-art electronics, online dark signal adjustment and the possibility to perform temperature compensation the BTS256-PAR represents the next generation photometer for all light measurement applications.

Easy Operation 
Using the BTS256-PAR is easy thanks to three function key operation and logical menu navigation. In standard measurement mode the meter automatically sets up and is ready to go. In expert mode the experienced user has access to all measurement parameters. 

Many Extra Useful Functions & Features

  • Time delay measurement allows user time to get out of the field of view when performing the measurement
  • The display can be automatically switched off during the measurement
  • End of measurement signal tone option
  • Illuminance distribution mapping using a computer generated layout with grids for single measurements. The measurement points can be sequentially executed and saved.
  • Fast data logger measurement mode that allows clocked reading taking from the photodiode with a measurement rate of up to a maximum of 100ms
  • Second data logger measurement mode that enables the clocked recording of all measured quantities including spectral measurement data
  • Date and time (real time clock) can be set
  • Tripod mount socket
  • Protective cap on detector

Use without PC 
The BTS256-PAR is equipped with all the functions necessary for computer-independent use of the device. The rechargeable batteries offer eight hours of operation. The USB adapter cable can be used to recharge the battery even without a PC. 

Use with PC 
A USB2 interface is provided for use with a PC enabling data exchange and battery recharging

User Software 
Supplied S-BTS256-E software offers all the functions necessary for measurement, display of readings and data transfer. The flexible desktop software concept enables the user to select which measurement value windows to display on the desktop. This can either be just a full screen display of lux measurement values or a matrix containing numerical and graphical display fields. Each desktop configuration can be saved for later use. 

Software Development Kit 
For self-programmers the S-SDK-BTS256 Software Development Tool option is available. The SDK is compatible with Lab View from National Instruments, NET from Microsoft and C/C++. The SDKs simplify incorporation of the BTS256-PAR into user based systems.

Available With A Powerful WiFi Interface
A BTS256-PAR WiFi version Light-Color-Spectral Meter comes with a powerful WiFi interface enables long distance wireless remote control of the light meter.

Who is the BTS256-PAR Light-Color-Spectral Meter Designed For?
This innovative yet affordable new lightmeter is ideal for anyone involved in lighting design and applications in plant growth, horticultural, animal husbandry, aquaculture, soil science any other agricultural field where light levels need to measured, monitored and controlled. It is essential tool for accurate measurement of LED based lighting. 

Product Specifications
For product specifications and configurable options for the BTS256-E, please visit the Gigahertz-Optik main website here.

To Order The BTS256-PAR Light-Color-Spectral Meter, Call Us Today At 1-978-462-1818.
Practical Solutions To Real LED Measurement Problems

Here's The Problem:
You are researching ways to extend the growing season for certain plants within a greenhouse. Experimentation with added artificial lighting like full-spectrum fluorescents and also LED based lighting to combat light starvation and promote plant growth is to be tested and analyzed.

Here Are The Requirements:

A simple to operate, accurate PAR,  light and color meter that can measure any type of light source accuracy in the greenhouse environment. It must be:

  • field portable / battery powered
  • on board memory to store readings
  • measure all current PAR measurands and spectral data
  • allow programming of custom PAR spectral weighting functions per end-user demands

Here's The Solution:
For complete PAR, color, spectral and absolute analysis of SSL and any other light source the BTS256-PAR Light-Color-Spectral Meter is the right tool.

Interested in discussing your LED measurement application? Give us a call!

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