Business Segments - Schedule of Revenue Information by Product (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 29, 2024	Jul. 01, 2023	Jun. 29, 2024	Jul. 01, 2023
Entity Wide Information Revenue From External Customer [Line Items]
Total revenues		$ 12,631	$ 12,855	$ 24,392	$ 26,561
Cyclo G6
Entity Wide Information Revenue From External Customer [Line Items]
Total revenues		3,336	3,658	6,289	7,327
Retina
Entity Wide Information Revenue From External Customer [Line Items]
Total revenues		7,295	6,857	14,069	14,071
Other
Entity Wide Information Revenue From External Customer [Line Items]
Total revenues	[1]	$ 2,000	$ 2,340	$ 4,034	$ 5,163

[1] (1) Includes service contract revenues of $0.1 million and $0.3 million, and $0.4 million and $0.8 million recognized during the three and six months ended June 29, 2024 and July 1, 2023, respectively. Includes $0.4 million and $0.7 million recognized revenue related to the exclusive distribution rights during both of the three and six months ended June 29, 2024 and July 1, 2023, respectively. Other also includes revenues from paid service, royalty, freight and legacy G probes.