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v3.23.3

Summary of Significant Accounting Policies (Details Narrative) - USD ($) | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Oct. 31, 2023 | Oct. 31, 2022 | Oct. 31, 2023 | Oct. 31, 2022 | Apr. 30, 2023 | Aug. 31, 2020
Product Information [Line Items] |  |  |  |  |  |
Cash and cash equivalents | $ 3,292,000 |  | $ 3,292,000 |  | $ 6,883,000 |
Short term investments | 15,427,000 |  | 15,427,000 |  | $ 27,790,000 |
Accretion of discount and amortization of premium on investments | 100,000 | $ 60,000.00 | 200,000 | $ (200,000) |  |
Accretion of discount and amortization of premium on investments | (100,000) | (60,000.00) | (200,000) | 200,000 |  |
Share-based compensation expense | 300,000 | 300,000 | 673,000 | 632,000 |  |
Revenue related to performance obligations satisfied over-time |  |  | 762,000 | $ 129,000 |  |
Revenue remaining performance obligation | 4,500,000 |  | $ 4,500,000 |  |  |
Expects to recognize revenue remaining performance obligation, percentage |  |  | 70.00% |  |  |
Expects to recognize revenue remaining performance obligation | 3,200,000 |  | $ 3,200,000 |  |  |
Antidilutive securities excluded from computation of earnings per share, amount |  |  | 7,294,852 | 6,242,465 |  |
Product development expense | $ 2,100,000 | $ 2,300,000 | $ 4,000,000.0 | $ 4,700,000 |  |
Patents [Member] |  |  |  |  |  |
Product Information [Line Items] |  |  |  |  |  |
Intangible asset estimated lives | 20 years |  | 20 years |  |  |
Trade Names [Member] |  |  |  |  |  |
Product Information [Line Items] |  |  |  |  |  |
Intangible asset estimated lives | 12 years |  | 12 years |  |  |
Customer Relationships [Member] |  |  |  |  |  |
Product Information [Line Items] |  |  |  |  |  |
Intangible asset estimated lives | 10 years |  | 10 years |  |  |
Transferred at Point in Time [Member] |  |  |  |  |  |
Product Information [Line Items] |  |  |  |  |  |
Revenue related to performance obligations satisfied over-time | $ 500,000 |  | $ 1,200,000 |  |  |
Transferred over Time [Member] |  |  |  |  |  |
Product Information [Line Items] |  |  |  |  |  |
Revenue related to performance obligations satisfied over-time | $ 400,000 |  | $ 900,000 |  |  |
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Three Customers [Member] |  |  |  |  |  |
Product Information [Line Items] |  |  |  |  |  |
Concentration risk percentage |  |  | 55.00% |  |  |
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Four Customers [Member] |  |  |  |  |  |
Product Information [Line Items] |  |  |  |  |  |
Concentration risk percentage | 71.00% |  |  | 69.00% |  |
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Five Customers [Member] |  |  |  |  |  |
Product Information [Line Items] |  |  |  |  |  |
Concentration risk percentage |  | 80.00% |  |  |  |
Santander Bank [Member] |  |  |  |  |  |
Product Information [Line Items] |  |  |  |  |  |
Deposits | $ 156,000 |  | $ 156,000 |  |  |
Santander Bank [Member] | January 2024 [Member] |  |  |  |  |  |
Product Information [Line Items] |  |  |  |  |  |
Letters of credit issued amount |  |  |  |  |  | $ 65,000

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