The Mysteries of Laser Mouse Size & Design

[cave_cat]

from online descriptions of laser mouse operating principle it's unclear to me that the mouse would need to be particularly big. Is the size of the mouse really based on ergonomics considerations and it could in practice be fit into much smaller case if we wanted to? Is the mouse actually mostly empty inside? Or is the current size important for making it from cheaper components than what would have been needed for a smaller design?

Also, so suppose we wanted to take an existing laser mouse and change its shape, such as in the best case to turn it into a pen shaped device like "Genius pen mouse" (TM). How hard would that be? Are the light source and sensor of the mouse straightforwardly extractable for installation in another device? How big are they? Are there any other components in the mouse that are "too big" and so would probably need to be placed outside the "pen mouse", such as in a "receiver" connected to the pen by a cable?

 

[yungman]

I always get smaller mouse, but not too small. I think ergonomics is the key. Not everyone is have good dexterity with their fingers, I personally would not want a super small mouse. If you hold up your index and middle finger, you'll see it is not much narrower than the smallest mouse on the market. That is one gating factor of the width.

If you open the mouse, you'll see battery take up a lot of space. Even 2 AAA batteries take up room. That is part of the gating factor of the length. Also if it is too short, you can't really have a good grip to maneuver the mouse.

Yes, if there is a good reason, it would be so easy to put all the circuits into one small IC and be done with it. If you don't mind spending money on batteries, you can always use watch batteries and make the mouse very small. I don't see any reason stopping people from shrinking the mouse technically.

 

[cave_cat]

If you open the mouse, you'll see battery take up a lot of space. Even 2 AAA batteries take up room.

most mice I have used are of the usb kind. Do they really have batteries inside as well? What's the point in having battery in usb device?

 

[yungman]

Sorry, mind freeze. I have been using wireless all along and that's the only ones I willing to use. I totally forgot about the ones still have a tail!

Still, ergonomics matters. Most people will have problem controlling very small mouse. You talked about something a pen size, try, hold a USB memory stick, imagine there are 3 bottons on it and try to slide around on the table and push the button, I bet you'll find it's hard to control. I just tried it before I post, it is very tiring on the fingers as I have to hold it pretty tight to avoid it slip around. It would be very hard to control precision pointing like what I use for CAD design. You might get carpal tunnel problem using such a small device.

Also, they used to sell smaller mouse, I don't see them in the last two years. There must be not enough sales to support it. Believe me, I like small mouse for carrying around. I just don't think anything smaller than what they used to sell is going to have a broad market. Even my little grandson always use a huge mouse! It's a rat to me!

 

[0xDEADBEEF]

Just buy a 10$ mouse and break it open. Unless you are customer of the big fruit store you can probably even screw your mouse open and look inside without damaging it. It is most certainly easy for a manufacturer to make something pen shaped. The main obstacle is probably to get the lighting right. The light one in a mouse is using a lot of space, and maybe you would have some tilt problems, but in the end the optical mouse is just a camera, and these days those are very small. The necessary chips can probably fit into an oversized usb plug.

 

[DragonPetter]

What's the point in having battery in usb device?

The point is for the device to operate wirelessly. The data is transmitted to and from the mouse and PC with a transceiver connected to the USB.

USB provides BOTH power and data communication, and it is a standard interface on PCs. By going with a battery and being wireless, you can maintain the standard data interface to the PC while still being powered.