With the time Circles of Light were discovered in different forms and there were combinations from the geometric figures from single forms of Circles of Light in the end, too. This enumeration doesn't like to be complete and not final but giving a good summary about the forms of Circles of light most of all which up till now are documented.

A. Circles of Light with a round outline
This form is most frequently sighted and at described as the "prototype". This form varies by the light cross in the middle appearing with respectively thinner arms. For narrow windows the complete form is also corresponding.
form102t1 form103t1 form104t1 form102at1 form103at1

These arms in the center also can crossover as if they entwine themselves or even leave the cross form - "parting" and forming a gap. At the coincidence points of these "light arms" characteristic points of light show up.
form106t1 form105t1 form110t1 form109t1  

At perfectly circular forms it also happens that the inner pattern appears to be an abbreviated cross or also to be almost a single point of light.
form107t1 form108t1      

On the other hand there are patterns of light to be found, in which the outline and the inner pattern are quite less apart. 

B. Forms with a rectangular outline
On a rather clear rectangle from light different inner forms appeared as they also are visible at A. with a round outline. The light rectangle on the other hand doesn't have a glowing edge.
form201t1 form202t1
form203t1 form204t1  

At square forms the inner light cross can have dead straight arms. Here it also comes to a small upright cross or can be even smaller just to appear as a point of light.
form205t1 form206t1      

C. Forms with diamond-shaped outline
At diamond-shaped outlines there was just a point of light or a more or less scaled upstanding cross to be found. 
form503t1 form502t1      

D. Further forms and combinations
One form is particular remarkable as it has a round outline and a simple rectangle inside either. Another form which very exceptionally and till now is rare, has a rounded off outline but is still almost rectangular and the inner pattern consists of light struts, that make a rectangle and at the corners, where they cross, create points of light. An other new form has no outline in the way the other geometric Circle of Light forms have. A circle form and a rectangle are overlaying, additional two (or more) light points were within. Other Circles of Light though seems to be created with three geometric figures.
form301t1 form401t1 form601t1 form701t1  

E. Patterns of Light
Some reflections of light have attracted attention because of their unusual form, even they are completely different as those characterized by geometrical forms.