Goodwill (Details) - USD ($)	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 5,900,000	$ 5,940,000
Currency translation on Hilger Crystals	(79,000)	(40,000)
Goodwill, Ending Balance	5,821,000	5,900,000
Innovation and Development [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	4,939,000	4,939,000
Currency translation on Hilger Crystals	0	0
Goodwill, Ending Balance	4,939,000	4,939,000
Optics [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	961,000	1,001,000
Currency translation on Hilger Crystals	(79,000)	(40,000)
Goodwill, Ending Balance	$ 882,000	$ 961,000

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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