Hi. I am a final year student of engineering and need all the help everyone can provide me with.I am supposed to make a vein locator in which 4 laser diodes are put in series and which operate on two 1.5V batteries. the laser diodes should have high intensity. however it should be noted that the light of all the 4 diodes should incident at a common point at the same time, making the light beam intensity all the more powerful.