Document and Entity Information - USD ($)	12 Months Ended
	Jun. 30, 2018	Sep. 10, 2018	Dec. 31, 2017
Document And Entity Information
Entity Registrant Name	LIGHTPATH TECHNOLOGIES INC
Entity Central Index Key	0000889971
Document Type	10-K
Trading Symbol	LPTH
Document Period End Date	Jun. 30, 2018
Amendment Flag	false
Current Fiscal Year End Date	--06-30
Entity a Well-known Seasoned Issuer	No
Entity a Voluntary Filer	No
Entity's Reporting Status Current	Yes
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		25,773,605
Entity Public Float			$ 47,403,296
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2018