Travis Brashears, Cameron Ramos and Serena Grown-Haeberli began collaborating at SpaceX, developing optical communications links that keep thousands of Starlink internet satellites in constant contact. Now, the three engineers are co-founders of Mesh Optical Technologies, a Los Angeles startup that announced a $50 million Series A led by Thrive Capital on Tuesday.  Mesh aims to mass-produce optical transceivers, devices that convert optical signals from fiber or laser into electrical signals