Scan angle doubling lens

[mixedgas]

latest tests:

See attached.

Image being scanned is unchanged, just the lens was inserted.

Sorry I jerked the camera a bit for the big one.

please keep in mind also the lens was not bolted down for this test, just hand held. It does better and cleaner lines then its doing in the pic.

Steve

[keeperx]

nice job.. how much loss?

[drlava]

the loss was probably around 40% because one of the optics in the path was IR coated. With the right coating there I expect the losses to be half that, maybe better. Sorry I couldn't hold all the lenses still

[buffo]

What power lens, Andrew?

I've had very good luck with a -2.75 power lens. I gave out a bunch of plastic ones at FLEM ver 5 back in March. They increase the beam diameter of course, but not too much. Graphics still look good, and so do beam shows, but it significantly reduces the power per unit area (irradiance) on your eyeballs when you're watching the show from within the danger zone.

Now that I've got a good power meter, I need to see if it gets my projector below the MPE of 10mw/cm2 limit at a distance of 20 ft (usual viewing distance at FLEM). If so, that would be very cool!

Adam

[allthatwhichis]

Now that I've got a good power meter, I need to see if it gets my projector below the MPE of 10mw/cm2 limit at a distance of 20 ft (usual viewing distance at FLEM). If so, that would be very cool!

Adam

[mixedgas]

What power lens, Andrew?

I've had very good luck with a -2.75 power lens. I gave out a bunch of plastic ones at FLEM ver 5 back in March. They increase the beam diameter of course, but not too much. Graphics still look good, and so do beam shows, but it significantly reduces the power per unit area (irradiance) on your eyeballs when you're watching the show from within the danger zone.

Now that I've got a good power meter, I need to see if it gets my projector below the MPE of 10mw/cm2 limit at a distance of 20 ft (usual viewing distance at FLEM). If so, that would be very cool!

Adam

Adam, I think your missing the point. When properly adjusted this doubles scan angle while maintaining beam diameter. Your looking at 3 scans spread out by my shaking the camera. This is a SPEED UP lens.


Steve

[drlava]

It does expand the beam about double but for a 2-3mm beam it doesn't come out too bad. Also, the colors stay aligned which is good for graphics.

Buffo, I don't think this lens has a power, really. But I get what you're saying about the negative focal length lens. Might have to try that sometime too

[drlava]

speaking of lenses, a cool projector add-on would be a 'lens' with zero power on the top half and negative(diverging) power on the bottom half for crowd scanning. Could be made simply by polishing a depression (or depressions) out of the bottom half of a glass hemisphere. The diverging bottom half could be for crowd scanning, yet the beams out of the top half would remain relatively untouched. And it's pretty fail-safe - no electronics

[allthatwhichis]

speaking of lenses, a cool projector add-on would be a 'lens' with zero power on the top half and negative(diverging) power on the bottom half for crowd scanning. Could be made simply by polishing a depression (or depressions) out of the bottom half of a glass hemisphere. The diverging bottom half could be for crowd scanning, yet the beams out of the top half would remain relatively untouched. And it's pretty fail-safe - no electronics

I like that idea...

[aijii]

would look a little wierd scanning projections that cross both segments of the lens though.

for instance, a vertical fan.

its bad (noticeable) enough with BAMS..

i wish BAMS had a gradient function...