Recent content by hl_world

5mW isn't strong for most lasers sold as "pointers" but it is decent for use as one to point at near objects. Burning lasers are in the 100s of milliwatts range but it also depends on the type of laser (wavelength, beam diameter, divergence). Divergence means the beam is more in the shape of a...

Thanks everyone.

Thanks. Could a point source be focused to infinity with the help of a parabolic mirror and maybe some lenses?

Is it possible to use a system of reflections to direct most (if not all) of the light from a small luminous sphere to produce a thin beam that can focus to infinity?

Consciousness is just an emergent process that has to be programmed, not an inherent property. Matter can be programmed because of inherent properties (electrons for atomic bonding, chemistry, electrical induction) but it requires these things to work in complexly specific ways. Think about it...

Since the 1st scale and its load are supported only by the 2nd scale, both scales should read M1. It would be 1/2 M1 for each if both scales were hanging directly on the wall sharing the load. Unless I misread.

475nm is bluish like this [●[/color]] but it isn't pure blue like this [●[/color]]. The NASA source you linked only gives rough values. I'm looking for the values of unbiased pure colours give or take 2 or 3 nanometers. ●[/color] 590nm: not orange like it says but amber (way closer to yellow...

Deep green light (especially from green lasers) always illuminates fluorescent surfaces with a red enough hue. It's widely mistaken that only UV light does this. Although some infrared light is still emitted with the green light if there is no IR filter which, apparently, is even more harmful...

475nm is way too cyanish. In fact, it's probably on the border between azure and sky blue. The problem with referring to the chromaticity diagram or any color on a screen is that it's all presented in RGB values and the accuracy of how it's coloured takes second place to the accuracy of its...

Thanks for the responses. @Danger I accept that there are differences in eye rods and visual cortices but there must be some reasonable degree of accuracy in where a group of people will say they see the purest blue. The problem with the palette/spectrometer thing is that it would...

Which wavelength of light will look blue without any bias toward cyan or violet? I know it's somewhere around 460nm but I don't know exactly where it is. And if you happen to know the same for green (not in any way cyanish or yellowish), please let me know.

Right, but smaller and localised on the mirror image.

I'll chew that one over. The optical illusion in the 3rd post gives the impression of grey dots where the white lines intersect. Their (grey dots) appearance & behavior of changing visibility depending on where you look resembles what I see around the fogged mirror image of my eyes even from...

It's possible I have high blood pressure but why would it cause these symptoms? To give you a better idea of what I see from a distance, the black I see is like the non existent grey dots in this optical illusion: Next time you leave the bath/shower, look at your reflection in the fogged...