Webopedia on Google+Webopedia on TwitterWebopedia on FacebookTech Bytes Blog
Main » TERM » U »

ultrasonic focus motor

Abbreviated as USM, and associated with digital camera terminology, ultrasonic motor (also called ultrasonic focus motor ) is a term that is mainly used to describe the motor that controls the movement of the lens or focus ring. An ultrasonic focus motor is much quieter (almost near-silent) and also moves the focus lens or ring faster when compared to a standard motor. A USM is able to hold the lens in place with precision and accuracy at the exact instant the lens arrives at the correct focus when using the camera's auto focus (AF) feature.

See "Digital Cameras" in the  Quick Reference section of Webopedia







TECH RESOURCES FROM OUR PARTNERS
LATEST ARTICLES
8 Agenda Apps to Help Students Stay Organized

Webopedia's student apps roundup will help you to better organize your class schedule and stay on top of assignments and homework. Read More »

20 Ways to Shorten a URL

If you need to shorten a long URL try this list of 20 free online redirection services. Read More »

Top 10 Tech Terms of 2015

The most popular Webopedia definitions of 2015. Read More »

STUDY GUIDES
Computer Architecture Study Guide

This Webopedia  study guide describes the different parts of a computer system and their relations. Read More »

Network Fundamentals Study Guide

Networking fundamentals teaches the building blocks of modern network design. Learn different types of networks, concepts, architecture and... Read More »

The Five Generations of Computers

Learn about each of the five generations of computers and major technology developments that have led to the current devices that we use today. Read More »