Fair Value Measurement (Details 1) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 29, 2012	Dec. 31, 2011	Dec. 31, 2010
Reconciliation of the changes in the Company's earn-out-cash (Level 3 liabilities) balance
Balance at the beginning of the period	$ 540		$ 380
Change in fair value of contingent consideration	195	55
Balance at the end of the period	719	540	380
RetinaLabs Acquisition [Member]
Reconciliation of the changes in the Company's earn-out-cash (Level 3 liabilities) balance
Payment made on earn-out - RetinaLabs	(241)	0
Ocunetics, Inc. acquisition [Member]
Reconciliation of the changes in the Company's earn-out-cash (Level 3 liabilities) balance
Addition of earn-out - cash related to Ocunetics, Inc. acquisition	$ 0	$ 105

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Amount of gain (loss) recognized in earnings, arising from liabilities measured at fair value on a recurring basis using unobservable inputs (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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- Definition

Purchases that have taken place during the period in relation to liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

+ Details

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- Definition

Settlements that have taken place during the period in relation to liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

+ Details

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- Definition

This element represents a liability measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

+ Details

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