Short answer: No
Long answer
Based on your description you are using HID mode, which means as far as the mobile phone is concerned the scanner is a keyboard. Logically, you don't need an on-screen keyboard if you have a physical one, so the virtual keyboard is hidden.
Work around
- iOS and Android
- Double click power button - the scanner will send a command to display the virtual keyboard if it detects a double click on the power button. Note: This is easier on the 7 series scanners
- jQuery input widget - there are jQuery plugins for different input types (e.g. a calendar modal for selecting a date). Maybe you can find or write an input widget to suit your needs.
- Android only
- Keyboard settings - certain versions of Android (4.2+) have the option to turn off the hardware keyboard. It's counterintuitive, but the physical keyboard will still work and the virtual keyboard will open on every input.