Figure 1: Spectral sensitivity
curves for PFG-04.
Figure 2: Diffraction efficiency
curve for PFG-04.
Figure 3: Hardening time for PFG-04
versus Storage Time. The black curve refers to a storage temperature of 18
Degrees Celsius and grey curve to a storage temperature of 4 Degrees
Celsius.
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This
material is designed for the recording of reflection Denisyuk-type
holograms using CW laser radiation (488nm, 514nm -Argon laser).
The material spectral sensitivity curve is shown in figure1.
The sensitivity reaches 100mJ/cm2 in the blue
spectrum range and 250mJ/cm2 in the green. Due to its
grainless structure, this material has very high resolving power
and a diffraction efficiency of >75% (figure2),
but has the lowest sensitivity from all holography emulsions
offered by Geola's distribution network.
The recommended processing
technique of the exposed hologram consists of the following
operations:
1). Thermal Hardening after
exposure (100OC) - Depending on the layer freshness.
See figure3.
2). Cooling to Room temperature.
3). Bathing in running filtered
water - 3mins.
4). Bathing in 50% Isopropyl
Alcohol solution for 2 - 3 mins.
5). Bathing in 75% Isopropyl
Alcohol solution for 2 - 3 mins.
6). Bathing in 100% Isopropyl
Alcohol solution for 2 - 3 mins.
7). Drying in a desiccator. (100OC)
for 60 mins.
8). Emulsion layer preservation
using optical anhydrous adhesive and protective glass.
Note that the processing solution
temperatures must not exceed 20OC for fresh layers.
If holograms appear "milky" in colour then the
processing solution temperature should be decreased or the
thermal hardening period should be prolonged. The material shelf
life is 12 months (average observed period).
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