Klein Convergence Gauge

Since 1983, Klein Instruments has manufactured the industry standard Klein Convergence Gauge. This gauge is so familiar, it is often known simply as the Klein gauge.

This small, handheld, opto-mechanical device is used to measure the convergence error between the lines of a CRT display. This sturdy, accurate tool is sufficient to obtain measurements that are invaluable to engineers, manufacturers, and quality inspectors. The CM7A series is made for monitors, the CM14A series is for medium-sized screens, and the CM28A series is for large-screen and rear-projection big-screen TVs.

The last letter of the model number designates whether the monitor reference color used to take readings is green or red. Whichever device is used, one gauge is sufficient to obtain measurements which are invaluable for engineering, manufacturing calibration verification, quality assurance, and incoming inspection.

The following models of Klein convergence gauges are available with the listed specifications. These models are all in stock and available, but manufacture has been discontinued. Supplies are limited.

Model Scale Range Scale mm/div Center Prism
CM7AG +-0.7mm 0.05mm Green
CM7AR +-0.7mm 0.05mm Red
CM14AG +-1.4mm 0.1mm Green
CM14AR +-1.4mm 0.1mm Red
CM28AG +-2.8mm 0.2mm Green
CM28AR +-2.8mm 0.2mm Red



The Klein K10-A has long been regarded as the industry standard in LCD calibration. It’s enhanced optics give it a 3X advantage in sensitivity over the original K-10 SF. Known for it’s superior speed, the K10-A can stream intensity data in 3.2 milliseconds and can provide color data in 125 milliseconds. The Klein K10-A is also extremely sensitive and color accurate. Large photo-diodes give the probe superior performance even in extremely low light (down to 0.00006 cd/m^2). Klein diodes are very large (5mm x 5mm each), thermally stable, and linear to report the highest degree of accuracy. The unparalleled speed and iconic design of this colorimeter have made it the most widely known Klein product.


Like all Klein colorimeters, the K10-A is ruggedly constructed with machined aluminum and high impact plastic. The K10-A’s auto ranging is solid state, and the housing is impact resistant to hold up to the 24 hours a day, 7 days a week usage that display manufacturers require. The K10-A’s compact size and light weight make transportation convenient. It is also fitted with a universal tripod mount for easy positioning and integration into workflows.


For maximum accuracy, not only is the f1’ of Y critical, but the accuracy of X and Z as well. Each diode has specially layered absorption filters designed for maximum color accuracy. Klein colorimeters are also rigorously tested to ensure that each device is thermally stable with an operating temperature range of 15-35 C.



The Klein K10-A also functions as an FFT (Fast Fourier Transform) flicker meter. The probe measures and integrates Y data in the head, streams in real time to the PC, and then the FFT is performed. The Klein K10-A can measure regular flicker between 1-150Hz. Multiple methods for displaying flicker data including JEITA, VESA, and contrast methods are selectable in the software. The Klein K10-A can be used to analyze any luminance source, including the common refresh-rate flicker in monitors, and random flashes caused by the transmission of current variations through solid state devices (LEDs). All flicker information can be logged and reported with Klein Chromasurf.