The light cone that I was describing till now will be observed when the actual focus point of the object lies beyond the sensor, i.e. the light rays from the object have still not converged when the plane of the sensor was encountered.
After the focus point is reached the rays crisscross and start diverging once again. Again this crisscrossing can be captured on the sensor by moving the focus point beyond the object. 
The sequence of images below were taken by moving the focus point behind the object of interest; here the LED.
In the first image of the sequence, the focus point was moved just behind the LED and we see a similar image as when the focus point was placed between the matchstick and the LED. But now the rays have actually crisscrossed which is not observed here since the cone is symmetric. To demonstrate the crisscross nature, I placed an opaque object and covered the left half of the lens, which made the right semicircle of the circular projection of the cone, disappear! To come back to our proper cone I moved the focus point back to the matchstick and did the same experiment. Now covering the left portion of the lens masks the left semicircle of the LED! This means there no crisscross!
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