Change of Focus for Liquid Crystals

Dylan Knight Rogers writes to tell us PhysicsWeb is reporting that US physicists have discovered a new liquid-crystal lens design that can alter the focus by varying the voltage applied. From the article: "The new lens, which has been built by Shin-Tson Wu and colleagues at the University of Central Florida, allows the focus to be changed in a new way. The device consists of a mixture of liquid-crystal molecules and smaller N-vinylpyrrollidone monomers placed between two glass substrates, each of which is coated with a thin transparent layer of conducting indium tin oxide. They then placed a concave glass lens with a flat base on top of one of the substrates."

Battery life...

[HateBreeder]

Picture it: A camera that could Auto-focus without any moving, mechanical parts.... faster and more energy efficient!

I wonder what's the percentage of power drained by a typical digital camera just for auto focusing under normal usage.

Re:Battery life...

[It'sYerMam]

Mobile phone cameras suck due to more than their auto-focus. The tiny CCD means they're susceptible to noise, and the lack of decent optics means they won't work well in low light or be able to zoom well - regardless of an autofocussing lens. Furthermore, because an expensive camera has an automatic user filter and learning curve, pictures taken with mobile phones are always likely to be, on average, crap, due to the lack of skill of the photographer.

eyes and lenses and such...

[ecalkin]

the human eye has a simple lens that provides focus on a curved (convex) surface. the good focus is right in the center and your eye moves around to maintain focus on whatever you're looking at.

    a regular camera Lens has many elements (glass pieces). even if you could make the glass 'variable', there would still be an amazing amount of complexity to make a clean sharp image on a flat surface (film or sensor).

eric

Augmented Reality

[jonnyboy777]

Perhaps this could help us on our way to stereoscopic head mounted displays that don't induce migraines after extended use (slight sarcasm here). Current technology primarily plays with parallax while keeping a fixed although often tunable focal distance, but LCDs with many microlenses could vastly help things. The perceived images would be much more realistic, as well.

Re:Neat.

[LiquidCoooled]

I hope you don't mean the flickering ones for viewing 3d movies.
These things would be horrendous for that, imagine the focal length bouncing backwards and forewards 30 times a second, I bet most people would throw up within minutes.

Eyeglass wearers would be better getting a hud by using the actual ground eyeglass as a substrate for the standard LCD screen than mess around with this dynamic focusing solution.

Re:Not for monitors just yet

[silentbozo]

If every pixel on the screen had its own lens that could throw the focus such that you'd have to focus either closer or farther, you could use the z-axis parameter in 3-d games (Half-life 2, for example) to render objects with different screen focus levels. It still wouldn't solve the problem of 3d, since both eyes would still perceive the same information - so there wouldn't be the overlap in view you would normally get from observing a real object, however you would get focal depth information.

What might be interesting is pairing this technology with 3D-goggles so you can finally combine the focus depth information with the overlap of two screens, for training applications.