Research grade measurement of photosynthetically active radiation (PAR), ePAR, PPF, and PPFD

Apogee Instruments Quantum sensors are the industry standard for measuring photosynthetically active radiation by agricultural professionals all over the world. We offer four types of quantum sensors; the Full Spectrum (blue head), the Original X (black head), the ePAR (silver head), and a Quantum Light Pollution Sensor (silver head).

The Full-spectrum Quantum Sensors are our top-of-the-line models and feature an advanced optical detector that provides the highest accuracy PAR (aka PPFD) measurements (400-700 nm) under all light sources, including all modern narrow-band LEDs.

Our Original X Quantum Sensors feature a less expensive optical detector that is accurate for measuring broadband light sources like the sun. This sensor, however, can have significant errors under LED fixtures, especially if they are blue/red in color or a high fraction of red color. For these applications, we recommend our full spectrum sensor.

Apogee's Extended Photosynthetically Active Radiation, or "ePAR" sensors are designed to make high-accuracy total photon flux intensity measurements of the newly recognized wider 400-750 nm ePAR range, which is a new photosynthetic radiation range some scientists are now measuring based on emerging research.

Our Quantum Light-Pollution Sensors are designed to be highly sensitive to light to detect small light leaks in the 340-1040 nm range that can disrupt plant dark periods in sensitive plants. The light-pollution sensors are very specialized sensors that will over-range under normal light levels.

For Apogee's 2-band sensors that measure PAR and Far-red, click here.
Apogee also offers a variety of meters and packages to measure daily light integral (DLI).

Full-Spectrum Quantum Sensors

Light Source
Provides accurate PAR measurements under all light sources, including LEDs.

Spectral Range
400 to 700 nm ± 5 nm (wavelengths where response is greater than 50 % of maximum)

Output Options
Available in multiple analog and digital outputs including unamplified, SDI-12, Modbus communication protocols, attached to a hand-held meter with a digital output, as a "smart" sensor that uses USB communication and custom software, or with Apogee's BlueTooth enabled microCache device.

Waterproof

ePAR Sensors

Light Source
Provides accurate measurements under all light sources.

Spectral Range
400 to 750 nm ± 5 nm (wavelengths where the response is greater than 50 % of maximum)

Output Options
Available in multiple analog and digital outputs including unamplified, SDI-12, Modbus communication protocols, attached to a hand-held meter with a digital output, as a "smart" sensor that uses USB communication and custom software, or with Apogee's BlueTooth enabled microCache device.

Waterproof

Full-Spectrum
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ePAR
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Original X
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Light Pollution
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Original X Quantum Sensors

Light Source
Economical choice for excellent accuracy under broadband light sources like sunlight, high pressure sodium, and certain metal halides, but not for colored LEDs--although post-measurement mathematical correction factors can be applied to improve accuracy under LEDs. Click here for LED correction factors you can apply to our original X sensors.

Spectral Range
370 to 650 nm (wavelengths where response is greater than 50 %)

Output Options
Available in multiple analog and digital outputs including unamplified, SDI-12, Modbus communication protocols, attached to a hand-held meter with a digital output, as a "smart" sensor that uses USB communication and custom software, or with Apogee's BlueTooth enabled microCache device.

Waterproof

Line Quantum Option
Measure a spatial average of PAR using a bar of 10 sensors.

Quantum Light Pollution Sensors

Light Source
Detects stray photons that disrupt night that are critical in preventing negative effects in plants such as hermaphrodism and stunted growth.

Spectral Range
340 to 1040 nm ± 5 nm (wavelengths where response is greater than 50 % of maximum)

Output Options
Available in multiple analog outputs, SDI-12 digital output, or with Apogee's BlueTooth enabled microCache device.

Waterproof

SQ-500 full-spectrum quantum sensor spectral response graph. — Research grade measurement of photosynthetically active radiation (PAR), ePAR, PPF, and PPFD

Apogee Instruments Quantum sensors are the industry standard for measuring photosynthetically active radiation by agricultural professionals all over the world. We offer four types of quantum sensors; the Full Spectrum (blue head), the Original X (black head), the ePAR (silver head), and a Quantum Light Pollution Sensor (silver head).

The Full-spectrum Quantum Sensors are our top-of-the-line models and feature an advanced optical detector that provides the highest accuracy PAR (aka PPFD) measurements (400-700 nm) under all light sources, including all modern narrow-band LEDs.

Our Original X Quantum Sensors feature a less expensive optical detector that is accurate for measuring broadband light sources like the sun. This sensor, however, can have significant errors under LED fixtures, especially if they are blue/red in color or a high fraction of red color. For these applications, we recommend our full spectrum sensor.

Apogee's Extended Photosynthetically Active Radiation, or "ePAR" sensors are designed to make high-accuracy total photon flux intensity measurements of the newly recognized wider 400-750 nm ePAR range, which is a new photosynthetic radiation range some scientists are now measuring based on emerging research.

Our Quantum Light-Pollution Sensors are designed to be highly sensitive to light to detect small light leaks in the 340-1040 nm range that can disrupt plant dark periods in sensitive plants. The light-pollution sensors are very specialized sensors that will over-range under normal light levels.

For Apogee's 2-band sensors that measure PAR and Far-red, click here.
Apogee also offers a variety of meters and packages to measure daily light integral (DLI).

Full-Spectrum Quantum Sensors

Light Source
Provides accurate PAR measurements under all light sources, including LEDs.

Spectral Range
400 to 700 nm ± 5 nm (wavelengths where response is greater than 50 % of maximum)

Output Options
Available in multiple analog and digital outputs including unamplified, SDI-12, Modbus communication protocols, attached to a hand-held meter with a digital output, as a "smart" sensor that uses USB communication and custom software, or with Apogee's BlueTooth enabled microCache device.

Waterproof

ePAR Sensors

Light Source
Provides accurate measurements under all light sources.

Spectral Range
400 to 750 nm ± 5 nm (wavelengths where the response is greater than 50 % of maximum)

Output Options
Available in multiple analog and digital outputs including unamplified, SDI-12, Modbus communication protocols, attached to a hand-held meter with a digital output, as a "smart" sensor that uses USB communication and custom software, or with Apogee's BlueTooth enabled microCache device.

Waterproof

Full-Spectrum
Learn More

ePAR
Learn More

Original X
Learn More

Light Pollution
Learn More

Original X Quantum Sensors

Light Source
Economical choice for excellent accuracy under broadband light sources like sunlight, high pressure sodium, and certain metal halides, but not for colored LEDs--although post-measurement mathematical correction factors can be applied to improve accuracy under LEDs. Click here for LED correction factors you can apply to our original X sensors.

Spectral Range
370 to 650 nm (wavelengths where response is greater than 50 %)

Output Options
Available in multiple analog and digital outputs including unamplified, SDI-12, Modbus communication protocols, attached to a hand-held meter with a digital output, as a "smart" sensor that uses USB communication and custom software, or with Apogee's BlueTooth enabled microCache device.

Waterproof

Line Quantum Option
Measure a spatial average of PAR using a bar of 10 sensors.

Quantum Light Pollution Sensors

Light Source
Detects stray photons that disrupt night that are critical in preventing negative effects in plants such as hermaphrodism and stunted growth.

Spectral Range
340 to 1040 nm ± 5 nm (wavelengths where response is greater than 50 % of maximum)

Output Options
Available in multiple analog outputs, SDI-12 digital output, or with Apogee's BlueTooth enabled microCache device.

Waterproof

DLI-400: PAR, Daily Light Integral, and Photoperiod Meter (Sunlight Only, 400-700 nm)

DLI-400: PAR, Daily Light Integral, and Photoperiod Meter (Sunlight Only, 400-700 nm)

$299.00

SQ-100X-SS: Original Quantum Sensor

SQ-100X-SS: Original Quantum Sensor

$219.00

SQ-202X-SS: Amplified 0-2.5 Volt Original Quantum Sensor

SQ-202X-SS: Amplified 0-2.5 Volt Original Quantum Sensor

$284.00

SQ-204X-SS Amplified 4-20 Milliamp Original Quantum Sensor

SQ-204X-SS Amplified 4-20 Milliamp Original Quantum Sensor

$284.00

SQ-205X-SS Amplified 0-5 Volt Original Quantum Sensor

SQ-205X-SS Amplified 0-5 Volt Original Quantum Sensor

$284.00

SQ-420X Smart Quantum Sensor | USB Output

SQ-420X Smart Quantum Sensor | USB Output

$259.00

AC-421 SDI-12 to USB Converter

AC-421 SDI-12 to USB Converter

$159.00

AC-422 Modbus to USB Converter

AC-422 Modbus to USB Converter

$184.00

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