Mr Crewe sadly lost his battle with cancer earlier this month.
A statement from Carl Zeiss said: “A well-known and respected individual, Michael’s personality was infectious. Through the strong relationships he built both personally and professionally, Michael’s passing will be a loss to both Carl Zeiss and the broader ophthalmic community.
“During his 25 years at Carl Zeiss, Michael became a key member of our team, who showed unerring loyalty to his work and to his customers, always going the extra mile to satisfy and support those who relied on him.
“His commitment, drive, loyalty and professionalism will remain in our memories and his time at Carl Zeiss will be recalled fondly by all.
“Michael (Bill) will be sadly missed by those who both knew and worked with him and our thoughts are with his family at this time.”