1. Passivation layer
Reflective layer
SMC mirrors - Technology Intermediate layer
• The structure is composed of one Substrate
isotropic, thermally conductive
material,
• There is no glass in the structure,
• The production process is fast (~2h)
and cheap (~0.7kEUR/m2)
• The manufacturing process
require two molds – steel
and glass one
• The technology is
applicable for SST (short
focal length) telescopes

2. Before coating
SMC mirrors – flat samples
manufacturing status
• Flat samples are prepared in the same
technology as mirrors prototypes
• 30 flat samples are ready for coating,
and later for shipping to WP MIR
After Al. + SiO coating –
campaign grid reflection
90
85
80
75
70
Reflectance [%]
65
60
55
50
45
40
35
30
25
300 350 400 450 500 550 600 650 700
Wavelength [nm]
Reflectance vs. wavelength

3. 7 mirrors (dark mirrors after Al coating)
Mirror prototypes –
manufacturing status
• 8 SMC mirrors was already
manufactured, 2 of them coated
• Size: hexagonal shape 40 cm (f2f)
• Focal length: ~20 m
• The coating process is delayed
due to chamber servicing
• First measurements was done – spot size is
about 25 mm in diameter
• Small and isotropic „halo” effect is visible
25mm
due to intermediate layer waviness
• We observe a problem with the mirror focal
length stability during thermal cycling