For that you need to check the Group multiple values and then set to show 1 values and set starting from 1. see the below screenshot for clarification

if you check the rewrite output of this filed you can see the token for that filed, for your case it would probably
[field_product_image_1]
So if you want to retrieve the image separately from the array, you have to do the above steps for each image, for example if you want the 3rd image, then you have to set starting from 2 and its tokes is [field_product_image_2]
, if you want 4th image, then you have to set starting from 3 and its token is [field_product_image_3]
.
Below screenshots will help you to understand easily.
I added each filed separately to retrieve each image

and its tokens and above method is for Drupal 6, you can do it in the same way for D7.
