CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Dec. 31, 2022	Jan. 01, 2022
Operating activities
Net income (loss)	$ (17,075,000)	$ 26,620,000
Adjustments to reconcile net income (loss) to net cash and cash equivalents provided by (used in) operating activities:
Depreciation and amortization	1,446,000	3,456,000
Net amortization (accretion) of investment premiums and discounts	(196,000)	109,000
Amortization of intangible assets	42,000	0
Gain on sale of Photonics division	0	(54,341,000)
Asset impairment charges	0	1,246,000
Equity-based compensation	4,890,000	4,003,000
Straight-line rent adjustment and amortization of lease incentives	(843,000)	(463,000)
Foreign currency loss on liquidation of entity	14,000	0
Loss on disposal of fixed assets	1,467,000	0
Deferred income taxes	836,000	25,000
Changes in assets and liabilities:
Accounts receivable	(1,528,000)	10,850,000
Inventories	(24,105,000)	9,597,000
Prepaid expenses and other assets	42,000	6,000
Accounts payable	6,290,000	(932,000)
Accrued payroll and other accrued liabilities	(1,266,000)	(1,972,000)
Customer advances	22,552,000	2,074,000
Total adjustments	9,641,000	(26,342,000)
Net cash and cash equivalents provided by (used in) operating activities	(7,434,000)	278,000
Investing activities
Purchase of investments	(52,385,000)	(17,148,000)
Proceeds from sales and maturities of investments	26,649,000	19,550,000
Purchase of Hia, Inc., net of cash acquired	(763,000)	0
Proceeds from sale of Photonics division	0	70,000,000
Purchase of leasehold improvements and equipment	(1,919,000)	(1,198,000)
Net cash and cash equivalents provided by (used in) investing activities	(28,418,000)	71,204,000
Financing activities
Proceeds from issuance of common stock	3,083,000	2,632,000
Taxes paid related to net share settlement	(724,000)	(734,000)
Net cash and cash equivalents provided by financing activities	2,359,000	1,898,000
Effect of exchange rate changes on cash	(331,000)	6,000
Net increase (decrease) in cash, cash equivalents and restricted cash	(33,824,000)	73,386,000
Cash, cash equivalents and restricted cash at beginning of period	103,514,000	30,128,000
Cash, cash equivalents and restricted cash at end of period	69,690,000	103,514,000
Cash paid (received) for:
Income taxes	569,000	559,000
Income tax refund	$ 0	$ (18,000)