Which company built Hubble's optical telescope assembly?

Perkin-Elmer built Hubble’s optical telescope assembly. NASA’s Marshall Space Flight Center commissioned the company to design and construct the telescope’s primary optical system, the part that gathers and focuses incoming light.

The optical telescope assembly was only one major piece of Hubble. Lockheed built and integrated the spacecraft structure, while other NASA centers managed instruments and operations. Perkin-Elmer also supplied Hubble’s Fine Guidance Sensors, which help the observatory point with extraordinary precision.

The company is especially associated with Hubble’s famous mirror problem. A manufacturing-test error left the primary mirror with a tiny but consequential shape error, causing spherical aberration. The flaw was diagnosed after launch in 1990, and astronauts corrected its effect during Servicing Mission 1 in 1993 with COSTAR and replacement instruments containing corrective optics.

A common mix-up is to credit Lockheed with the telescope itself. Lockheed built the spacecraft bus; Perkin-Elmer built the optical telescope assembly inside it.