for my project i am using max3799 IC and VCSEL.I have designed 4.layer PCB board and assembled max3799 IC and VCSEL also all other passive components specified in max3799 IC datasheet. this max3799 IC has 17 registers to modify according to requirements. Using rasp-pi i can successfully access registers and modify them.

for reference i am attaching datasheet of VCSEL and PIC1, PIC2 about forward voltage.

TO drive VCSEL it needs forward voltage of 2V and forward current of 6mA. but i am getting forward voltage of 1.15 V and forward current of 7.8 mA. So, VCSEL is not lasing.

PIC1 shows ideal working condition when VCSEL connected to MAX3799 IC 

PIC2 shows my board working condition when VCSEL connected to MAX3799 IC

[enter image description here](https://i.stack.imgur.com/m0IzN.png)[![enter image description here](https://i.stack.imgur.com/OTEzB.jpg)](https://i.stack.imgur.com/OTEzB.jpg)