| Company Name | Type | Status |
|---|---|---|
| OPTEK CO., LIMITED | Private company limited by shares | Live |
| ADVANCED OPTEK CO., LIMITED | Private company limited by shares | Live |
| OPTEK ELECTRONICS COMPANY LIMITED | Private company limited by shares | Live |
| Optek Technology Limited | Private company limited by shares | Dissolved |
| OP-TEK TECHNOLOGY LIMITED | Private company limited by shares | Live |
| DAE YANG OPTEK LIMITED | Private company limited by shares | Live |