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N-Pen N 100

N-Pen is a light-weight, battery-powered reflectance-based instrument that provides a convenient, cost-effective method for effective nitrogen management in plants throughout their growing season. Essentially, the N-Pen characterizes nitrogen amount by means of reflectance and by the concept of a close link between chlorophyll content and nitrogen content in plants.

Rugged and compact N-Pen can be favorably used in the field, in the plant biology lab or for education. The use of the N-Pen is non-destructive and permits quick, repeated measurements throughout the growing season. It takes four AAA alkaline batteries and is supplied in a robust case.

N-Pen versions with a PC communication module - Bluetooth or USB - are also available. Comprehensive FluorPen 1.0 software provides data transfer routines and many additional features for data presentation in tables and graphs.

Currently Available Calibrations:

  • Maize
  • Wheat
  • Barley

  • Lightweight, hand-held design
  • Non-invasive measurement method
  • Easy two-button operation
  • Quick and easily repeatable measurements
  • Battery-operated
  • N-Pen
  • Significant yield increase
  • Quick tuning of nitrogen management in crops
  • Increasing nitrogen use efficiency
  • Reducing the risk of yield-limiting N deficiencies
  • Saving labor and/or application costs
  • Reducing the risk of excessive fertilizer applications and subsequent contamination of the environment
  • Agronomy research
  • Maize
  • N-Pen measures actual nitrogen content using the Normalized Difference Greenness Index NDGI
  • Nitrogen reading is calibrated for particular plant (wheat, barley or maize) and is displayed as %
  • Variety or hybrid differences can greatly affect N-Pen readings
  • Plant diseases, nutrient deficiencies and other kinds of plant stress can also affect N-Pen readings
  • NPen NPen
  • Simply insert the leaf between the leaf clip and the optical tip
  • N-Pen collects and stores individual readings and calculates the average automatically
  • Readings should be taken on different plants of the same species
  • Readings should be taken on the 2nd (maximum 3rd) youngest leaf on each plant
  • Readings should be taken on about the same location on each leaf (close to the mid part)
  • FluorPen 1.0 software for data loading, processing, and visualization in a PC (optional)
  • Bluetooth or USB communication module (optional)
  • GPS mapping plug-in (optional)
  • Measured Parameters:
    Nitrogen content calibrated for particular plant
  • Measuring Light:
    Dual wavelength light source - 565 nm, 760 nm
  • Optical Aperture Diameter:
    5 mm
  • Detector Wavelength Range:
    500 to 800 nm bandpass filters
  • Memory Capacity:
    Up to 16 Mb
  • Display:
    2 x 8 characters LC display
  • Keypad:
    Sealed, 2-key tactile response
  • Keypad Escape Time:
    Turns off after 8 minutes of no use
  • Power Supply:
    4 AAA alkaline or rechargeable batteries
  • Battery Life:
    48 hours typical with full operation
  • Low Battery Detection:
    Low battery indication displayed
  • Size:
    170 x 57 x 30 mm; 6.7" x 2.2" x 1.2"
  • Weight:
    180 g, 6.5 oz
  • Operating Conditions:
    Temperature: 0 to 55 ºC; 32 to 130 ºF. Relative humidity: 0 to 95 % (non-condensing)
  • Storage Conditions:
    Temperature: -10 to +60 ºC; 14 to +140 ºF. Relative humidity: 0 to 95 % (non-condensing)
  • Warranty:
    1 year parts and labor
  • KLEM K. (2008): Prediction of spring barley nutrition state and grain quality using spectral reflectance and chlorophyll fluorescence. Precision Agriculture – ICPA 2008


  • Orders and Payments
  • N-Pen N 100
    699,- €
  • N-Pen N 100/USB
    1.199,- €
  • N-Pen N 100/BT
    1.349,- €
  • Substitute USB Communication Cable *
    39,- €
  • GPS Module *
    249,- €
  • Battery Charger *
    49,- €
  • Self-Adhesive Rubber Pads
    12,- €

Other N-Pen Versions

N-Pen N 100
Standard N-Pen version with no PC communication module. Data are saved in the device internal memory only.

N-Pen N 100-B
Standard N-Pen version supplemented the with Bluetooth communication module and FluorPen 1.0 software for data transfer to a PC.

N-Pen FP 100-U
Standard N-Pen version supplemented with the USB communication module and FluorPen 1.0 software for data transfer to a PC.

Optional Features and Accessories

GPS Module
To record the exact location of the measurements performed by the pen-category instruments.

Small, portable notebook (type according to current availability on the market).

Substitute USB Communication Cable
Substitute USB cable allowing connection between the "pen" devices and a PC (the device is delivered with one USB cable, which is included in the device price).

Battery Charger
Includes battery charger and 4 AAA alkaline rechargeable batteries. EU norm only.

Self-Adhesive Rubber Pads
One set includes 10 solid pads (to be attached to the clip) and 10 pads with an opening (to be attached at the optical head).


FluorPen 1.0
OS: Windows 2000 / Windows XP / Windows 7 (32bit, 64bit) / Windows 8 (32 bit, 64bit)/ Windows 10 (32 bit, 64bit),
Language: English
Size: 11.1 MB

OS: Windows 7 (32bit, 64bit) and higher
Language: English
Size: 901 KB

USB Driver for Pen Devices
OS: Windows
Language: English
Size: 2.3 MB

FluorPen Series Manual
Type: PDF
Language: English
Size: 4.7 MB

FluorPen - List of References
Type: PDF
Language: English
Size: 904 KB

FluorPen Explain
Type: PDF
Language: English
Size: 2.8 MB

SpectraPen SP 100 Manual
Type: PDF
Language: English
Size: 1.4 MB

SpectraPen SP 100 - List of References
Type: PDF
Language: English
Size: 131 KB

SpectraPen LM 500 Manual
Type: PDF
Language: English
Size: 2.9 MB

PolyPen Manual
Type: PDF
Language: English
Size: 2.2 MB

PolyPen - List of References
Type: PDF
Language: English

AquaPen Manual
Type: PDF
Language: English
Size: 4.1 MB

AquaPen Manual (Czech)
Type: PDF
Language: English
Size: 4.0 MB

AquaPen - List of References
Type: PDF
Language: Czech
Size: 1.1 MB

LaiPen Manual
Type: PDF
Language: English
Size: 2.0 MB

LaiPen - List of References
Type: PDF
Language: English
Size: 135 KB

N-Pen Brief Guide
Type: PDF
Language: English
Size: 104 KB

N-Pen - List of References
Type: PDF
Language: English

PlantPen NDVI-PRI Operation Manual
Type: PDF
Language: English
Size: 2.7 MB

PlantPen - List of References
Type: PDF
Language: English
Size: 181 KB

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PlantPen PRI 200 & NDVI 300

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- Photosynthesis Research & Education
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N-Pen N 100

N-Pen is a light-weight, battery-powered instrument that provides quick measurement of actual nitrogen content in plants throughout their growing season.
- Significant Yield Increase
- Quick Tuning of Nitrogen Management in Crops
- Saving Nitrogen Application Costs

LaiPen LP 100

LaiPen is a light-weight, battery-powered device that mesures Leaf Area Index (LAI) and Photosynthetically Active Radiation (PAR). It provides fast and easily repeatable measurements with instant readouts that can be exported to a PC for further processing.
- Studies of Canopy Productivity
- Studies of Forest Dynamism
- Remote Sensing

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