Equity Compensation Plans (Details - ESPP Fair value assumptions) - Employee Stock Purchase Plan [Member] |
12 Months Ended | ||
|---|---|---|---|
Apr. 30, 2023 |
Apr. 30, 2022 |
Apr. 30, 2021 |
|
| Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] | |||
| Risk-free interest rate | 3.76% | 0.15% | 0.14% |
| Expected life (in years) | 6 months | 6 months | 6 months |
| Expected volatility | 68.60% | 59.91% | 75.50% |
| Expected dividend yield | 0.00% | 0.00% | 0.00% |