Logitech MX Anywhere Mouse (Tracks on Glass)

The Logitech Anywhere Mouse MX
works on virtually any surface

The Logitech Anywhere Mouse MX works wherever you do. Thanks to Logitech Darkfield Laser Tracking, you'll get precise cursor control on virtually any surface, even glass tables (4 mm minimum thickness) where optical and standard laser mice fail. You can take it anywhere thanks to its compact size. The tiny Logitech Unifying receiver is small enough to leave in your notebook. Anywhere you go, you'll get things done more comfortably with its sculpted design. You get hyper-fast scrolling to fly through long documents and Web pages with a single spin of the scroll wheel. Plus thumb buttons let you go back and forth between Web pages with just a click.

Tiny Logitech Unifying receiver stays in your notebook.

When sitting at a desk or table, many people choose to add peripherals such as a notebook mouse and keyboard to their computing setup to make it more comfortable. But when it comes time to change locations (e.g. heading home from the office), these peripherals need to be unplugged and each of their USB receivers stored somewhere safe.

To solve this problem, Logitech introduced the Logitech® Unifying receiver – a tiny wireless receiver that’s so small it can stay plugged into a laptop at all times and can be paired with up to six compatible Logitech keyboards and mice. Logitech Unifying products are easily identified by the Unifying icon, which appears on the products themselves, as well as on the pre-paired, bundled receiver.

There's no need to unplug it when you move around, so there's less worry of it being broken or lost.

Shattering the glass barrier – A Technical Background

Comparison of Dark Field LASER tracking
against traditional LASER and LED systems

All optical and laser mice use irregularities in the work surface to track the direction and speed of your mouse. The more irregularities on the surface, the easier it is for the sensor to track your movements. But there just aren't enough irregularities on clear glass for your standard mouse to work.

Beginning in 2005, Logitech – the world’s leading manufacturer of computer mice – embarked on a multiyear research and development project to create a mouse that could overcome these limitations. After considering many options – including Doppler radar, UV imaging and interferometry techniques – Logitech® Darkfield Laser Tracking was developed.

Traditional microscopes – that use standard, or bright field, illumination – direct the light into the objective lens. But sometimes the tiny objects underneath the microscope lack contrast under normal illumination. For example, biologists often see this challenge when viewing small organisms in a liquid habitat; the contrast between the fluid and the organisms is not great enough for the microscope to detect.

To help scientists see objects that are very tiny and not sufficiently contrasted in the surface environment, dark field illumination was invented. Instead of collecting and focusing the light from points directly beneath the surface of the lens, dark field illumination blocks out the central area of light and only allows rays of light to enter the lens from an angle. If there are no objects beneath the microscope, the entire field will appear dark. But when the light hits a particle, it scatters the light into the lens at an angle. The resulting image has a dark background with bright objects on it, similar to a starry sky, and this is where the technique gets its name.

How Dark Field Illumination works on both
opaque and transparent surfaces.
Click here for a larger image

To achieve dark field illumination, Logitech mice with Darkfield Laser Tracking use two lasers to more effectively collect microscopic details of the tracking surface. When the mouse is used on a regular surface – such as a formica table or a piece of paper – the texture of the surface provides plenty of detail for the lasers to track and requires only one of the lasers to be used. But for high-gloss surfaces that don’t have enough details, such as a glass tabletop, the mouse sensor views the surface itself as black and, instead, tracks the dust and other residuals that appear on the surface. In this case, two lasers are used. The diagram to the left shows a visual representation of how dark field illumination works on both an opaque and a transparent surface.

Compatible with Windows 8

Just as a scientist would use a dark field microscope in a lab, a Logitech mouse with Darkfield Laser Tracking illuminates the surface beneath the mouse at an angle, and collects and focuses that light back into the lens. Any small particles, such as dust or micro-scratches, are cast against a black background. Similar to the way that our eye sees the clear night sky, the mouse’s sensor sees the clean areas of glass as a dark background with bright dots – the dust. Then, the sensor interprets the movement of these dots to track exactly where you’ve moved the mouse. Diagram 5, above, provides a visual of this concept.

Because of its ability to detect the tiniest of particles, Darkfield Laser Tracking allows your mouse to track virtually anywhere. But because it requires some micro-details to work, it won’t work on a surface that’s perfectly clean and smooth. However, outside of scientific laboratories, such a surface is extremely rare.