Leaf area meters measure the surface area of a leaf without damaging the leaf, so the same plant can be measured again over time. High-resolution optical scanners capture the leaf, and real-time measurement shows results quickly. Multi-leaf mode speeds up large sample sets, and compound leaves and seedlings can be measured. Built-in data storage and USB output support record keeping. A touchscreen or PC interface controls the work. Adjustable settings and calibration suit different leaf sizes and types. Typical uses include crop breeding, plant physiology, plant disease studies, climate change research, forestry, horticulture and teaching labs.