Hey, delete does mean delete, maybe you can get your permanently deleted photos back to your iPhone in the following ways.
While you deleted your photos on iPhone accidentally, try to get them back in iCloud if you have a backup files before. Check your "Recently Deleted" folder in "Album", those deleted photos can be restored within 40 days. Or you can restore them by logging on your iCloud via web browser.
If this method doesn't work, you have another option, which is to recover them with a backup files in iTunes. But insure that the last backup is earlier before you deleted phones, and notice that your iPhone will lose all newly added files. However, few people will back up their files in iTunes.
But unfortunately if you didn't restore your deleted photos via the above two ways, there are a few iPhone Data Recovery programs out there that can help you restore your photos.
For further reference, see the tutorial about how to restore deleted photos on iPhone. Good luck!🙂