Do you have any photos on the iPad? That is the slide show icon. Usually it will start up a random slide show of all the photos you have saved.
I love it as it's like having a digital picture frame to look at when I'm not using the pad for other things.
If you don't want the slide show icon on the lock screen you can turn it off. Go to settings, passcode lock, and you will see the picture frame on/off button. In the settings list you will see the options for how the slide show will work.
it is there when you turn it on, the blank screen. i understand the icons showing on the home page. This has just happened, must not be making the problem clear. Thanks.