Table 1.
Specifications of the ELI-NP Laser Beam Circulator Mirrors
Wavelength, nm | AOI, ° | Reflection | Thickness, nm | Aperture, mm | Flatness PTV |
515
| 22.5 |
| 10 | 30 |
(
over 80% aperture) |
515
| 45 |
| 13 | 50.8 |
(
over 75% aperture) |
515
| 15 |
| 19 | 76.2 |
(
over 60% aperture) |
515
| 45 |
| 19 | 76.2 |
(
over 60% aperture) |
Table 2.
Typical Parameters of the Designed Mirrors
Function | AOI, deg | Number of Layers | Total Thickness, nm |
Mirror
| 15 | 33 | 2556.85 |
Mirror
| 22.5 | 33 | 2556.85 |
Mirror
| 45 | 37 | 3068.78 |
Antireflection coating
| 15 | 3 | 427.8 |
Antireflection coating
| 45 | 9 | 584.3 |
Table 3.
Theoretical Reflection Coefficients of the Different Mirrors for Different Incidence Wavelengths and Incidence Angles
Mirrors at 15° |
|
|
|
30° | 15° | 30° | 15° |
515 nm
| 99.998 | 99.996 | 99.987 | 99.993 |
532 nm
| 99.996 | 99.996 | 99.97 | 99.994 |
Mirrors at 22.5
|
|
|
|
22.5
|
30
|
22.5
|
30
|
515 nm
| 99.998 | 99.997 | 99.992 | 99.987 |
532 nm
| 99.998 | 99.996 | 99.99 | 99.969 |
Mirrors at 45°
|
|
|
|
|
|
|
515 nm
| 99.99 | 99.98 |
532 nm
| 99.99 | 99.965 |
Table 4.
Estimated Performance at 515 nm Deduced from Measurements at 532 nm
Number of Fabricated Mirrors | Rs | Rp |
AOI = 15° |
11
| Mean | 99.963 | 99.951 |
STDV | 0.003 | 0.002 |
AOI = 22.5°
|
80
| Mean | 99.967 | 99.962 |
STDV | 0.005 | 0.007 |
AOI = 45°
|
31
| Mean | 99.976 | 99.952 |
STDV | 0.003 | 0.004 |
Table 5.
Average Flatness Performance of the Large-Aperture Mirrors
Front-Side Coating | Rear-Side Coating | Diameter | Number of Samples | Average Flatness | Standard Deviation Flatness |
Mirror | Mirror | 50 and 75 mm | 26 | 19.4 nm | 4.3 nm |
Mirror | Antireflection coating | 50 and 75 mm | 16 | 18.9 mm | 5.3 mm |
Table 6.
Typical Parameters of the Designed Bandpass Filters
Specifications | BPF1 | BPF2 |
Substrate material
| Fused silica | Fused silica |
material
|
|
|
material
|
|
|
Number of layers front face
| 170 | 34 |
Number of layer rear face
| 92 | 58 |
Thickness front side, µm
| 11.4 | 3.4 |
Thickness rear side, µm
| 13.7 | 3.5 |
Table 7.
Typical Wavelengths Used for Monitoring the Two Faces (Front Face, FF, and Rear Face, RF) of the Bandpass Filters
Coating | BPF1, FF | BPF1, RF | BPF2, FF | BPF2, RF |
Number of monitoring glasses
| 6 | 3 | 1 | 4 |
Number of monitoring wavelengths
| 7 | 8 | 2 | 7 |
Table 8.
Typical Parameters of the Designed Filters with Broadband Controlled Transmission
Specifications | EF1 | EF2 |
Substrate material
| Fused silica | Fused silica |
material
|
|
|
material
|
|
|
Number of layers front face
| 30 | 67 |
Thickness front side, µm
| 2.3 | 4.9 |
Number of monitoring glasses
| 1 | 2 |
Number of monitoring wavelengths
| 2 | 4 |