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Mice and Keyboards (1)
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Just about every computer in the land needs a keyboard, and most need a mouse. Let's call them K&M from now on, it saves me typing time! In the old days the choice of K&M was very limited, usually to the one the manufacturer gave you when you bought the computer. Now it's all different with the advent of cordless K&M, optical mice and so on.
So what's on offer these days? Well, you can stick with the original K&M if you want to, some computer manufacturers are 'giving away' optical mice with the computer, some even have cordless keyboards as standard. So what's the advantage? Let's have a look at each one. |
Standard Ball Mice
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If you turn over your mouse you may see a rubber ball poking its nose out of the bottom of the mouse. Move the ball and the cursor on your screen moves as well - very exciting. Surrounding the ball is a rotating widget that holds it in place, remove the widget and the ball drops out (probably onto the floor). Have a look inside the mouse and you will see three plastic wheels. If you have had the mouse for some time, these wheels will probably be covered in a film of goo. This goo needs to be carefully removed with a sharp implement like a modelling knife blade.
Once removed, the goo needs to be removed from the inside of the mouse, try blowing it out, preferably not with a tyre inflating hose line. When you replace the ball and the widget, you will find the mouse is working so much better, the cursor moves around the screen easier, and you have just saved yourself 5 + VAT. Thank you, you're welcome. We have just touched on the major disadvantage of the standard ball mouse. It attracts goo on the inside, and if left un-treated, will eventually stop working. Apart from that, ball mice are great, and they are as cheap as chips to replace if you do manage to break one. |
Optical Mice
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A lot of users are now opting for the optical mouse, I certainly have. There are two types, corded and cordless. Personally I opt for the corded type as I never really get on with cordless mice except with my laptops when I loath having wires dangling all over the place.
The main difference between a ball mouse and an optical mouse can be seen if we turn over the mouse (again) and have a look. The ball has gone and has been replaced by a red light source. An optical mouse uses a light-emitting diode and photodiodes to detect movement relative to the underlying surface, rather than moving some of its parts - as in a mechanical mouse. |
As computing power grows cheaper, it has become possible to embed more powerful special-purpose image-processing chips in the mouse itself. This advance enabled the mouse to detect relative motion on a wide variety of surfaces, translating the movement of the mouse into the movement of the pointer and eliminating the need for a special mouse-pad. This advance paved the way for widespread adoption of optical mice.
Modern surface-independent optical mice work by using an optoelectronic sensor to take successive pictures of the surface on which the mouse operates. Most of these mice use LEDs (Light-Emitting Diodes) to illuminate the surface that is being tracked; LED optical mice are often mislabeled as 'laser mice'. Changes between one frame and the next are processed by the image processing part of the chip and translated into movement on the two axes using an optical flow estimation algorithm.
Optomechanical (ball) mice detect movements of the ball optically, giving the precision of optical without the surface compatibility problems, whereas optical mice detect movement relative to the surface by examining the light reflected off it.
Which Type?
Optical mice supporters claim that optical rendering works better than mechanical mice, that it requires no maintenance and that optical mice last longer due to having no moving parts. Optical mice do not normally require any maintenance other than removing debris that might collect under the light emitter, although cleaning a dirty mechanical mouse is fairly straightforward too.
Supporters of mechanical mice point out that optical mice generally cannot track on glossy and transparent surfaces, including many commercial mousemats, causing them to periodically 'spin' uncontrollably during operation. Mice with less image-processing power also have problems tracking extremely fast movement, though high-end mice can track at 1 m/s (40 inches per second) and faster.
Since optical mice render movement based on an image which the LED illuminates, use with multi-colored mousemats may result in unreliable performance. However, optical models will outperform mechanical mice on uneven, slick, squishy, sticky or loose surfaces, and generally in mobile situations lacking mouse pads. The advent of affordable high-speed, low-resolution cameras and the integrated logic in optical mice provides an ideal laboratory for experimentation on next-generation input-devices. Experimenters can obtain low-cost components simply by taking apart a working mouse and changing the optics or by writing new software.
The Third Way
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Some gamers and people with mouse-handling challenges prefer to use something like a rollerball or trackball mouse, which is really different from 'standard' mice by being stationery on the desk, and is used by rolling the ball on the top of the device to move the cursor, then clicking on the buttons either side of the ball.
As I mentioned earlier, this device is very helpful if you have something like arthritis and moving a ball or optical mouse around the desk is challenging. In other cases, the mouse is useful where space is at a premium, and you simply don't have the room to move a mouse around a mousemat. Thirdly, I have known some died-in-the-wool gamers who wouldn't use anything else. It takes all sorts I suppose. |