|  |

| |

Enabling better global research outcomes in soil, plant & environmental monitoring.

ACCUPAR Ceptometer model LP-80

Measure Canopy PAR and Calculate LAI

The ACCUPAR model LP-80 is a lightweight, portable, linear photosynthetically active radiation (PAR) sensor. It lets you measure canopy PAR interception and calculate leaf area index (LAI) at any location within a plant or forest canopy.

ACCUPAR LP-80 Features
Lightweight, Self-contained

The ACCUPAR weighs a little over 1 pound (0.5kg). The attached controller, powered by four AAA batteries, can be used to take measurements manually or can log data unattended for short periods of time. It stores 1 MB of data (over 2,000 readings) for later download and analysis.

Includes External Sensor

The included external PAR sensor can be used to make simultaneous above- and below-canopy PAR measurements. Using both the external sensor and the ACCUPAR together allows you to get accurate PAR and LAI data in clear, partly cloudy, or overcast sky conditions.


  • Greenhouse Management
  • Biomass Production
  • Canopy Cover
  • Plant Ecology

The ACCUPAR can be operated in environments with temperatures from 0° to 50°C, and in relative humidities of up to 100%. The instrument ships with an RS-232 interface cable to allow for downloading data to a computer, an external PAR sensor to allow for calibration, and simultaneous above and below canopy PAR measurements. The ACCUPAR operates on four AAA alkaline batteries.

The ACCUPAR model LP-80 is a menu-driven, battery-operated linear PAR ceptometer, used to measure light interception in plant canopies, and to calculate Leaf Area Index (LAI). It consists of an integrated microprocessor-driven data logger and probe. The probe contains 80 independent sensors, spaced 1 cm apart. The photosensors measure PAR (Photosynthetically Active Radiation) in the 400 to 700 nm waveband. The ACCUPAR displays PAR in units of micro-mols per meter squared per second (µmol m2s1). The instrument is capable of hand-held or unattended measurement.


Data Storage Capacity 1 MB RAM (over 2,000 measurements)
Number of Sensors 80
PAR Range 0 to > 2,500 µmol m-2s-1
Resolution 1 µmol m-2s-1
Probe Length 84 cm
Overall Length 99 cm (40 in)
Unattended Logging Interval User selectable, between 1 and 60 min
Instrument Weight 0.56 kg (1.23 lbs)
Data Retrieval Direct via RS-232
Keypad 6 key, menu-driven
Operating Environment 0-50°C (32-122°F), 0-100% relative humidity
External PAR Sensor Cable Length 5 meters
Interface Cable RS-232 cable
Power Four AAA Alkaline cells
Minimum Spatial Resolution 1 cm
AccuPAR Ceptometer References
Andrade, F.H., Calviño, P., Cirilo, A. and Barbieri, P. 2002, ‘Yield Responses to Narrow Rows Depend on Increased Radiation Interception’, Agronomy Journal, vol. 94, pp. 975-980.

Baez-Gonzalez, A.D., Kiniry, J.R., Maas, S.J., Tiscareno, M., Macias, J., Mendoza, J.L., Richardson, C.W., Salinas, J. and Manjarrez, J.R. 2005, ‘Large-area Maize Yield Forecasting using Leaf Area Index Based Yield Model’, Agronomy Journal, vol. 97, pp. 418-425.

Blaser, B.C., Gibson, L.R., Singer, J.W. and Jannink, J. 2006, ‘Optimizing Seeding Rates for Winter Cereal Grains and Frost-Seeded Red Clover Intercrops’, Agronomy Journal, vol. 98, pp. 1041-1049.

Campbell, G.S., Use of the AccuPAR Ceptometer to Quantify Effects of Riparian Vegetation Removal on Stream Energy Balance. Washington, Decagon: 1-3.

Gibson, L.R., Singer, J.W., Vos, R.J. and Blaser, B.C. 2008, ‘Optimum Stand Density of Spring Triticale for Grain Yield and Alfalfa Establishment’, Agronomy Journal, vol. 100, no. 4, pp. 911-916.

Girona, J., Mata, M., del Campo, J., Arbonés, A., Bartra, E. and Marsal, J. 2006, ‘The use of Midday Leaf Water Potential for Scheduling Deficit Irrigation in Vineyards’, Irrigation Science, vol. 24, pp. 115-127.

Hyer, E. and Goetz, S.J. 2004, ‘Comparison and Sensitivity Analysis of Instruments and Radiometric Methods for LAI Estimation: Assessments from a Boreal Forest Site’, Agricultural and Forest Meteorology, vol. 122, no. 3-4, pp. 157-174.

Lopez, G., Mata, M., Arbones, A., Solans, J.R., Girona, J. and Marsal, J. 2006, ‘Mitigation of Effects of Extreme Drought During Stage III of Peach Fruit Development by Summer Pruning and Fruit Thinning’, Tree Physiology, vol. 26, no. 4, pp. 469-477.

Maddonni, G.A., Cirilo, A.G. and Otegui, M.E. 2006, ‘Row Width and Maize Grain Yield’, Agronomy Journal, vol. 98, pp. 1532-1543.

Nyakatawa, E.Z., Reddy, K.C. and Mays, D.A. 2000, ‘Tillage, Cover Cropping, and Poultry Litter Effects on Cotton: II. Growth and Yield Parameters’, Agronomy Journal, vol. 92, pp. 1000-1007.

Scanlon, B.R., Reedy, R.C., Keese, K.E. and Dwyer, S.F. 2005, ‘Evaluation of Evapotranspirative Covers for Waste Containment in Arid and Semiarid Regions in the Southwestern USA’, Vadose Zone Journal, vol. 4, pp. 55-71.

Stancioiu, P.T. and O’Hara, K.L. 2005, ‘Regeneration Growth in Different Light Environments of Mixed Species, Multiaged, Mountainous Forests of Romania’, European Journal of Forest Research, vol. 125, no. 2, pp. 151-162.

Tewolde, H., Sistani, K.R., Rowe, D.E., Adeli, A. and Tsegaye, T. 2005, ‘Estimating Cotton Leaf Area Index Nondestructively with a Light Sensor’, Agronomy Journal, vol. 97, pp. 1158-1163.