XML 69 R57.htm IDEA: XBRL DOCUMENT v3.25.2

Fair Value (Gain)/Loss on Derivative - Investor Options (Tables)

12 Months Ended

Jun. 30, 2025

Material income and expense [abstract]

Summary of Fair Value Gain/Loss On Derivative Investor Options

		2025				2024				2023
		US$(000's)				US$(000's)				US$(000's)
Fair value (gain)/loss on derivative - investor options in September 2023 (2023 Investor options)			(14,344	)			11,193				—
Fair value (gain)/loss on derivative - investor options in June/July 2024 (2024 Investor options)			(13,928	)			31				—
Fair value (gain)/loss - investor options converted to shares			(11	)			—				—
Total fair value (gain)/loss on derivative - investor options			(28,283	)			11,224				—

X

- References

No definition available.

+ Details

Name:	ifrs-full_MaterialIncomeAndExpenseAbstract
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Disclosure of tabular information about fair value gain/loss on derivative investor options explanatory.

+ References

No definition available.

+ Details

Name:	opt_DisclosureOfTabularInformationAboutFairValueGainLossOnDerivativeInvestorOptionsExplanatory
Namespace Prefix:	opt_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration