CD resolution?

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Updated: 2005-03-28 by HoloM (the god)
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JohnFP

CD resolution?

Post by JohnFP »

What is the resolution of standard off the shelf recordable CD's? Anyone know?
Dinesh

CD resolution?

Post by Dinesh »

I have DVD specs. Since I'm pretty sure you have some holographic idea in mind (possibly the same one I had, hence the collection of following data!), DVD would be finer than recordable CD's. I'm at home right now and have CD specs at work. I'll post those also.
DVD:
Thickness:1.2mm (+/-0.30)
Substrate Thickness: 0.6mm(+0.043/-0.03)
Spacing Layer Thickness: 55microns (+/-15)
Mass: 13 to 20g(12-cm disc)
Diameter: 120mm(+/-0.30)
Spindle Hole Diameter: 15mm(+0.15/-0.00)
Clamping Area Diameter:22 to 33mm
Inner guardband diameter:33 to 44mm
Burst Cutting Area Diameter: 44.6mm(+0.0/-0.8) to 47(+/-0.10mm)
Lead-in Diameter: 45.2 to 48mm(+0.0/-0.5)
Data Diameter: 48mm(+0.0/-0.4) to 116mm
Lead-out Diameter: 70mm min to 117mm max
Outer Guardband diameter: 117mm to 120mm
Radial runout (disc): <0.3mm peak-to-peak
Radial runout (track): <100microns peak-to-peak
Refractive index:1.55(+/-0.10)
Birefringence:0.10microns max
Reflectivity:45 to 85%
Readout wavelength:640nm(+/-15)
Polarization:Circular
Numerical aperture: 0.60(+/-0.01 with objective lens)
Beam diameter:1.0mm(+/-0.2)
Optical spot diametr:0.59microns (+/-0.01)
Tilt margin (radial):+/-0.8 degrees
Track Spiral (outer layer):Clockwise
Track pitch: 0.74 microns (+/-0.01 avg, +/-0.03max)
Pit Length: 0.4 to 1.866 microns
Data bit length(avg):0.2667 microns
Channel bit length: 0.1333microns (+/-0.0014)
Jitter: ,8% of clock period
Maximum Local defects: 100micron (air bubble, 300 micron (black spot), no more than 6 defects between 30 and 300 microns in any 80mm scanning distance
Rotation: Counterclockwise
Now, homework for tonight: Calculate the maximum angle between beams at 488nm to be able to record a fringe in the above medium. For extra credit, determine the possible scatter (hint: reflectivity can be obtained via Fresnel equations by using the refractive index datum).


Tom B.

CD resolution?

Post by Tom B. »

Estimate the sensitivity of the medium in Joules per cm^2, both at the peak dye sensitivity wavelength of ~650 nm and at 488 nm.

Sergio

CD resolution?

Post by Sergio »

Some DVD's use the cyanine dye correct for 650nm absorption, the dye will bleach after exposure, and the plastic substrate melt to record the pitch lines, the heat required is high, you mean bleach the dye to record the hologram?
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