SCHOTT® Solar Glass 0787
As one of the harshest environments known to man, space demands materials and equipment that can perform under the most demanding conditions. An ECSS space-qualified material, SCHOTT® Solar Glass 0787 has been uniquely designed for these conditions, helping spacecraft to push the limits of human knowledge.
A cerium-doped material composition enables SCHOTT® Solar Glass 0787 to block harmful UV radiation that threaten spacecraft and the technology they rely upon. While blocking UV light, SCHOTT® Solar Glass 0787 still achieves a high transmittance in the visible spectrum of light up to near-infrared, without loss of transmittance from the effects of solarization.
SCHOTT’s decades of experience and expertise in glass manufacturing allows SCHOTT® Solar Glass 0787 to be produced in several different thicknesses directly drawn from the melting tank. This includes ultra-thin and flexible glass, cut into large sheets or custom sizes. Design opportunities are further enhanced with the availability of different coatings.
Stable, protective and long-lasting
SCHOTT® Solar Glass 0787 offers a range of technical advantages when used for space applications such as photovoltaic systems and optical solar reflectors. Transmittance across the spectrum from UV-A to near-infrared is excellent, while low wavelength UV and particle radiation are effectively blocked. Low solarization also ensures reliable performance during the lifetime of a mission, while a fire-polished surface and outstanding geometrical homogeneity add to its effectiveness.
SCHOTT® Solar Glass 0787 offers a range of technical advantages when used for space applications such as photovoltaic systems and optical solar reflectors. Transmittance across the spectrum from UV-A to near-infrared is excellent, while low wavelength UV and particle radiation are effectively blocked. Low solarization also ensures reliable performance during the lifetime of a mission, while a fire-polished surface and outstanding geometrical homogeneity add to its effectiveness.
Outstanding transmission
High absorption UV radiation
Protection against particle radiation
Made to withstand solarization
High edge strenght
Fire-polished surface
SCHOTT® Solar Glass 0787 is available as:
- Cut-to-Size Substrates
- Unpolished Substrates and Wafers
SCHOTT developed Solar Glass 0787 to meet the demands of space exploration and research, combining protection and function to enable a range of applications. With the option of additional coatings plus a range of sizes and thicknesses, SCHOTT® Solar Glass 0787 is versatile, reliable and highly effective.
The use of photovoltaic solar cells is central to spacecraft function. However, radiation in space gradually degrades those cells, reducing their efficiency. SCHOTT® Solar Glass 0787 is the ideal cover glass for photovoltaic cells, minimizing damage while maintaining high light transmission in the visible and near-infrared ranges. Anti-reflective coatings can also be applied to the glass, increasing transmission levels further.
Thermal management in spacecraft is vital, with the temperature needing to be carefully regulated and heat exchange maintained. For effective heat exchange, a spacecraft requires efficient thermo-optical surfaces. When applied with a reflective coating, SCHOTT® Solar Glass 0787 is a highly effective thermo-optical surface, protecting against harmful solar radiation while facilitating heat exchange thanks to high emittance in the infrared range.
Specially designed for use in the space exploration field, SCHOTT® Solar Glass 0787 has a wide range of technical advantages. These ensure long-lasting, stable performance and a continuing dual role, both protecting and enhancing the function of spacecraft for the entire length of their mission – and beyond.
1. Protection against harmful radiation
To ensure a space system functions well throughout the duration of a mission, its technology and hardware need to be effectively protected against particle radiation and UV-B and UV-C rays. SCHOTT® Solar Glass 0787 reflects that harmful light and minimizes the damage it causes.
2. High, homogenous light transmission
Across the radiation spectrum from UV-A to NIR, SCHOTT® Solar Glass 0787 achieves an outstanding level of transmission. This enables high performance and efficiency of photovoltaic systems, which spacecraft depend upon to function at the optimum level.
3. Stable solarization over a mission’s lifetime
The constant harmful radiation all materials are exposed to in space means that degradation is always a threat. The special material composition of SCHOTT® Solar Glass 0787 is designed to prevent solarization or discoloration of the glass, enabling a stable optical performance for the lifetime of the mission.
4. High surface quality, excellent geometrics
The stable and reliable performance of a glass depends on its geometrical properties, and SCHOTT has the expertise to deliver top quality. All thicknesses and shapes are drawn with a fire-polished surface and homogenous geometry, producing consistently great results.
1. Protection against harmful radiation
To ensure a space system functions well throughout the duration of a mission, its technology and hardware need to be effectively protected against particle radiation and UV-B and UV-C rays. SCHOTT® Solar Glass 0787 reflects that harmful light and minimizes the damage it causes.
2. High, homogenous light transmission
Across the radiation spectrum from UV-A to NIR, SCHOTT® Solar Glass 0787 achieves an outstanding level of transmission. This enables high performance and efficiency of photovoltaic systems, which spacecraft depend upon to function at the optimum level.
3. Stable solarization over a mission’s lifetime
The constant harmful radiation all materials are exposed to in space means that degradation is always a threat. The special material composition of SCHOTT® Solar Glass 0787 is designed to prevent solarization or discoloration of the glass, enabling a stable optical performance for the lifetime of the mission.
4. High surface quality, excellent geometrics
The stable and reliable performance of a glass depends on its geometrical properties, and SCHOTT has the expertise to deliver top quality. All thicknesses and shapes are drawn with a fire-polished surface and homogenous geometry, producing consistently great results.
| Geometrical properties | ||
|---|---|---|
| Thickness | Thickness Tolerance | Thickness Variation (TTV) |
| 0.075 mm | ± 0.015 mm | ≤ 0.030 mm |
| 0.100 mm | ± 0.015 mm | ≤ 0.030 mm |
| 0.125 mm | ± 0.015 mm | ≤ 0.030 mm |
| 0.150 mm | ± 0.015 mm | ≤ 0.030 mm |
| Optical properties | |
|---|---|
| Refractive index nd for coverglass (as drawn) |
1.5080 ± 0.003 |
| Total normal emittance εn of coverglass top surface at 25 °C |
≤ 0.86 |
| Thermal properties | |
|---|---|
| Transformation temperature Tg | 568 °C |
| CTE (Coefficient of thermal expansion) α | 8.5 ∙ 10–6/K (20 °C; 300 °C) |
| 7.9 ∙ 10–6/K (20 °C; 150 °C) | |
| Mechanical properties | |
|---|---|
| Density ρ (annealed at 40 °C) |
2.51 ± 0.05 g/cm³ |
| Young's modulus E | i70.0 kN/mm² |
| Poisson's ratio µ | 0.216 |
| Breaking Strength | Strength-optimized cutting process, details available on request |
| Electrical properties | |
|---|---|
| Bulk resistivity ρD | > 1 ∙ 1011 Ω m (ν = 20 °C) |
| Spectral transmittance (λ = 200 nm to 3200 nm and 200 nm to 500 nm) |
|---|
| Transmittance Values for Glass Thickness 150 μm | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| τ (λ) – individual values in % | τ in % arithmetic mean for the given λ range | ||||||||
| τ400 | τ450 | τ500 | τ600 | τ300-320 | τ400-450 | τ600-800 | τ450-1100 | τ900-1800 | |
| Uncoated glass | 91.3 | 91.7 | 91.8 | 92.0 | 11.4 | 91.5 | 92.2 | 92.2 | 92.3 |
| Coated glass, single side anti-reflex |
92.3 | 93.4 | 94.0 | 94.4 | 11.5 | 92.9 | 94.3 | 94.0 | 93.3 |
| Coated glass, single side anti- reflex, τ into adhesive |
95.8 | 97.0 | 97.5 | 98.0 | - | 96.5 | 97.9 | 97.7 | 96.7 |
Note: Non-toleranced numerical values are reference values of a typical production quality
