Hi, graham.
Did you enable iCloud on your iPhone? If so, you can login your iCloud account on your new model and sync the photos from iCould to your new iPhone.
Or if you have already backup your old phone to iTunes before it was broken, then you can restore the entire backup to your new device with iTunes. Anyway, it is still possible to extract specific data like your pictures from the iPhone backup.
If unfortunately you have never backed up your old iPhone with any means, I'm afraid that you have to find an iPhone data recovery tool to get them back, otherwise you have no way to regain them.
The above are all the methods that you can do to recover pictures from your broken iPhone.