One of my inventions

[Matty2sum]

I am looking for an option on my Laser Ruler. it an old idea that never made it.

[insane_alien]

its a pretty cool idea pity it can only be used from a set distance though. be awesome if it was variable.

[5614]

At first I misread this, I thought you wanted to point a laser at the wall and using the time taken for the last beam to come back you would calculate how far away the wall is. But that's not what you mean.

 

It is a clever idea, however I see two immediate issues that may arise. Firstly as i_a said, it will only work at one set distance (unless those lens are variable*). For best accuracy you would need another ruler to measure the distance between the laser and the object you are projecting the ruler onto. And secondly how clear the ruler image is. You don't want the laser to diffract a lot as this would give the ruler a fuzzy edge. If the 1cm mark looked like this:

then you would have a problem.

 

*Of course theoretically you could get an automatically adjusting lens. You'd need to measure the distance and then use that information to change the shape of an electronically sensitive lens. However this would be very complex.

[blike]

The biggest hurdle would be convincing people the laser ruler is better than a conventional 6" piece of plastic which is by far more durable.

[Klaynos]

Wouldn't be too hard to create some nice optics to draw the line for a variable length, set on a dial, or more accurately a digital display...

 

Nice idea, could probably build a little prototype using a laser level you can buy in diy stores...

[Dak]

^ what klaynos said about variable optics.

 

a few other problems, especially in a DIY use: it could only accurately be used on properly flat surfaces, as otherize the projection (and thus the measurement) would become distorted, and also it couldn't be used on planes of the same colour as the projection.

 

also can't use it to draw a strait line

[padren]

Since you are rendering a rectangle image onto a plane, you would need it capable of measuring the distance to three contact points (and that still assuming the target is flat) and modifying the places the laser lines are drawn to account for distance and distortion.

If you needed to manually set the distance it would be impossible to get the angle and distance accurate enough to work.

 

If you *could* manually adjust how long the ruler was so it could work like a measuring tape - that would be very cool. If you had one dial for ruler length and another for setting a laser mark on a spot within it, you could easily compare lengths that should be similar or mark boards etc with it.

 

The main drawback is with a ruler or tape measure you don't have to worry about the "0" mark sliding around, because its pressed up to something, but even a slightly shakey hand would cause havoc at any distance over a few inches.

[Matty2sum]

yea my next idea gose to hightes bider

 

JJ yea it hasz some flaws. i made a shoebox with a halogen light and a paper lens yea yea i know i was geting prity good resoults untill it cought fire lol.

 

do you supose if you mixed a glow stick with bubbles= glowing-bubbles?

[science_nerd]

yea my next idea gose to hightes bider

 

JJ yea it hasz some flaws. i made a shoebox with a halogen light and a paper lens yea yea i know i was geting prity good resoults untill it cought fire lol.

 

do you supose if you mixed a glow stick with bubbles= glowing-bubbles?

 

I would think so. If you mix up the glow sticks chemicals with some bubbles as long as the chemical content of the bubbles don't react with the stick chemicals, it would be glowing bubbles, but would probably with a little less glowing intensity as almost more water is added...

 

As to glow sticks chemical content, I found them from this glow sticks online place under FAQ:

 

4 g Sodium Carbonate

0.2 g Luminol

0.5 g Ammonium Carbonate

0.4 g Copper Sulfate Pentahydrate

approx. 1 litre of Distilled Water

50 ml of 3% Hydrogen Peroxide

 

I would think you would be basically adding more water to the content.

[DrP]

[quote=Dak;307315

 

also can't use it to draw a strait line

 

 

That - and you wont be able to have play sword fights with it in maths classes when you get bored.

[npts2020]

That - and you wont be able to have play sword fights with it in maths classes when you get bored.

 

"I'll have to get to work on a laser ruler right away." said the curmudgeonly schoolmaster.

[insane_alien]

That - and you wont be able to have play sword fights with it in maths classes when you get bored.

 

light saber fights!