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LaiPen LP 100

LaiPen LP 100 measures Leaf Area Index (LAI), which is defined as the one-sided green leaf area per unit ground surface area (LAI = leaf area / ground area, m2 / m2) in broadleaf canopies. The LaiPen LP 100 calculates LAI and other canopy structure attributes from solar radiation measurements made with a wide-angle optical sensor. Measurements made above and below the canopy are used to determine canopy light interception at five angles, from which LAI is computed using a model of radiative transfer in vegetative canopies.

The LaiPen was designed by scientists and engineers to provide its user quick and reliable results. Unlike in other similar devices measuring LAI, the LaiPen LP 100 is accurate in most daylight conditions and does not require cloud cover or specific sun angles for its proper performance.

LaiPen LP 100 can work in two operation modes:
- Single sensor mode - reference measurement is taken before, after or during measurement with the same instrument
- Two sensor mode - second instrument is used for automatic logging of reference signal

LaiPen LP 100

  • Leaf Area Index (LAI):
  • Photosynthetically Active Radiation (PAR):
    Photosynthetically Active Radiation measured as Photosynthetic Photon Flux Density (PPFD)
  • LaiPen LP 100
  • High sensitivity
  • Integrated sensor for measuring foliage inclination
  • Measurement in five different acceptance angles - light is taken from five different zenith angles with one reading
  • Fast and easily repeatable measurements with instant readouts
  • Manual and automatic measurement
  • Lightweight, robust and battery-powered device with simple two-button operation
  • Large internal data storage
  • USB communication
  • External GPS module (optional)
  • LaiPen LP 100
  • Studies of canopy growth and productivity
  • Studies of forest dynamism
  • Research on air pollution or insect impact on foliage health
  • Great for rapid, repeated measurements and for large plant screening programs
  • Remote sensing
  • Global carbon cycle
  • LaiPen LP 100
  • Comprehensive software with data collection, analysis and visualization
  • USB communication
  • Visualization and data transfer routines to Microsoft Excel
  • Regular firmware updates
  • GPS mapping plug-in (optional)
  • Measured Parameters:
    - Leaf Area Index (LAI)
    - Photosynthetically Active Radiation (PAR)
  • Detector Wavelength Range:
    - 400 to 700 nm bandpass filters for PAR measurement
    - 400 to 500 nm bandpass filters for LAI measurement
  • View Restricting Cap:
    - Horizontal field of view: 112º
    - Vertical field of view: 16º
  • Foliage Inclination of Measurement:
    View angles: 0º, 16º, 32º, 48º, 64º
  • 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:
    120 mm x 57 mm x 30 mm 4.7" 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
  • POKORNÝ, R., TOMÁŠKOVÁ, I., HAVRÁNKOVÁ, K. (2008): Temporal variation and efficiency of LAI in young mountain Norway spruce stand. European Journal of Forest Research. Volume 127, Pages 359-367. DOI: 10.1007/s10342-008-0212-z
  • JONCKHEERE I., FLECK S., NACKAERTS K. ET AL. (2004): Review of methods for in situ leaf area index (LAI) determination. Part I. Theories, sensors and hemispherical photography. Agricultural and Forest Meteorology. Volume 121, Pages 19-35. DOI: 10.1016/j.agrformet.2003.08.027
  • NILSON, T. AND KUUSK, A. (2004): Improved algorithm for estimating canopy indices from gap fraction data in forest canopies. Agricultural and Forest Meteorology, Volume 124, Pages 157–169. DOI:10.1016/j.agrformet.2004.01.008
  • WEISS, M., BARET, F., SMITH, G. J., JONCKHEERE, I., COPPIN, P. (2004): Review of methods for in situ leaf area index (LAI) determination. Part II. Estimation of LAI, errors and sampling. determination. Agricultural and Forest Meteorology, 121 (1-2): 37–53. DOI:10.1016/j.agrformet.2003.08.001
  • POKORNÝ, R. AND MAREK, M. V. (2000):Test of accuracy of LAI estimation by LAI-2000 under artificially changed leaf to wood area proportions. Biologia Plantarum 43 (4): 537-544. DOI: 10.1023/A:1002862611176


  • Orders and Payments
  • LaiPen LP 100/USB
    1.999,- €
  • Mini-Computer *
    390,- €
  • Standard Tripod *
    39,- €
  • Carrying Rod *
    39,- €
  • Substitute USB Communication Cable *
    39,- €
  • GPS Module *
    249,- €
  • Battery Charger *
    49,- €

Optional Features and Accessories

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

Standard Tripod
Tripod holder providing with the flexibility to pick the ideal location for automatic readings in open plot.

Carrying Rod
Rod for measuring above shrubs and undergrowth.

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

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

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).


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- Studies of Canopy Productivity
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