1991 D Linclon Penny DDO?

I'm thinking Die Deterioration Doubling, not DDO. Possible split plating with the mint mark. Full, sharp, high-resolution photos of the coin's obverse and reverse would be welcome--helps us get a better sense for what's going on with the piece. Thanks.

Depending on what side of the devices you are asking the question about. If the side facing the rim, that would be DDD ( Die Deterioration Doubling) But if you asking about the left side of the date devices, you could get a different answer. There are 2 or three different answers to what you are seeing that you question?

Well the reverse images are showing Machine Doubling on the bottoms of the devices. So I'm guessing you are looking at the tops of the devices on the obverse. (just opposite the reverse). So you are probably seeing Machine Doubling there as well. The issues with your images is not the light, but the light glaring. You need to use a diffuser to remove the glare factor. Depending on your light source this can be fixed easily. The light is either reflecting off the flat devices on the obverse, caused by the Machine Doubling. But if you need assistance to fix this issue, an image of your setup would help with the suggestion for you.