One major part in the model payload for ESAs BepiColombo mission to planet mercury is the BepiColombo Laser Altimeter (BELA) for the characterisation of the topology of the planets surface. For a European space mission, this is a new technology. The concept of the BELA instrument is based upon the classical altimeter approach of a direct detection of travel time of a high energy laser pulse from the orbiter towards the planets surface and back.
From the BELA instrument proposal towards ESA, the following measurement excitation approach can be extracted:
- As laser source, a solid state laser system in Master Oscillator Power Amplifier configuration with passive q-switching for short pulse generation is foreseen
- By the use of optical fibers, a longitudinal optical pumping configuration inside this Oscillator-Amplifier Box (OAB) can be achieved with a mechanically and thermally separated Pump Diode Unit (PDU)
- This Pump Diode Unit is electrically driven from a Power & Control Electronics unit, called Laser Electronics Unit (LEU), which serves also as electrical interface towards the remaining instruments units and boxes
vH&S has performed the Phase A/B study including the design, fabrication & verification of a prototype model (PM).