Fruit Diameter Measuring Instrument

The fruit diameter measuring instrument is a compact, handheld device designed to measure the curvature radius and surface displacement of fruit and similarly curved specimens with high precision. It quantifies the radius of a curved surface by detecting the linear displacement of its measuring claws, delivering a direct radius readout so researchers and growers can assess fruit size, uniformity, and development without complex calculation. Five interchangeable sets of measuring jaws (spans 10, 20, 30, 60 and 100) suit different arc surface radii and accuracy needs, and the gauge measures outer and inner arc surface radius as well as depth, with inner diameter, outer diameter and high-precision percentage modes.

It combines fine resolution (0.005 mm) with low radius measurement error (ΔR ≤ 0.01 × R/S), which suits studies that compare fruit geometry across growth stages, cultivars or treatment groups. Its displacement measurement error is held to ΔS ≤ 0.02 mm, and radius accuracy is better than 1%.

Typical applications include pomology research, plant-breeding trials, post-harvest quality assessment, and agronomic field studies where repeated, non-destructive measurement of individual fruit is required. The instrument operates across a working temperature range of 0 to 40 °C and is unaffected by relative humidity up to 80%, supporting both laboratory benchtop use and field conditions.

Each unit ships as a complete package including five interchangeable measuring claws, two CR2032 lithium batteries, an instruction manual, and a protective plastic storage case. Optional accessories—including USB and RS232 data cables and an external display—are available for researchers who need to log or transmit measurement data directly.