Signs of Laylat al-Qadr
Question

Can Laylat al-Qadr be seen, i.e. can it be seen with the human eye? Some people say that if a person can see Laylat al-Qadr he sees a light in the sky and so on.
How did the Messenger of Allah (peace and blessings of Allah be upon him) and the Sahabah (may Allah be pleased with them all) see it? How can a person know that he has seen Laylat al-Qadr? Will a person still gain its reward even if he could not see that night? Please explain that to us, and mention the evidence for it.
Praise be to Allah.Can we see Laylat al-Qadr?
Laylat al-Qadr may be seen with the eye, for the one whom Allah helps to see it. That is by seeing its signs. The Sahabah (may Allah be pleased with them) used to recognize it by its signs. But not seeing them does not mean that one will not gain its reward, if one spends that night in prayer out of faith and the hope of reward. 
The Muslim should strive to seek it in the last ten nights of Ramadan, as enjoined by the Prophet (peace and blessings of Allah be upon him), hoping to earn reward. 
If it so happens that a person spends this night in prayer out of faith and seeking reward, then he will gain its reward, even if he does not know that that was Laylat al-Qadr. 
The Prophet (peace and blessings of Allah be upon him) said: “Whoever spends the night of Laylat al-Qadr in prayer out of faith and seeking reward, all his previous sins will be forgiven.”
According to another report: “Whoever spends that night in prayer, seeking Laylat al-Qadr, then he catches it, his previous and future sins will be forgiven.” 
What are the signs of Laylat  al-Qadr? 
And a sound report from the Prophet (peace and blessings of Allah be upon him) indicates that the sign of Laylat al-Qadr is that the sun rises on the following morning with no visible rays. 
Ubayy ibn Ka’b used to swear that it was the night of the twenty-seventh, citing this sign as evidence. 
When is Laylat al-Qadr? 
The more correct view is that Laylat al-Qadr moves through all the last ten nights, but it is most likely to be one of the odd-numbered nights, and the night of the twenty-seventh is the most likely among the odd-numbered nights. 
Whoever strives in worship during all of the last ten nights, praying, reading Quran, making du’a and other kinds of good deeds will undoubtedly catch up with Laylat al-Qadr and attain what Allah has promised to those who do that out of faith and seeking reward. 
And Allah is the Source of strength, May Allah bless our Prophet Muhammad and his family and Companions.
And Allah knows best.