Adam Lambert has declared a ''new era'' with the announcement of his new single 'New Eyes'.

The 37-year-old star took a break from his solo career four years ago to go on tour with Queen and made his comeback in February with the single 'Feel Something', which saw him address coming out of a ''dark period'' where he became ''depressed''.

The 37-year-old singer had been struggling with pressure in his career to ''compromise on [his] artistic vision'' that led to him ''second-guessing'' himself and entering into a downward spiral.

However, now he has teased a whole new chapter, kicking off with 'New Eyes', which is released on May 15.

He tweeted: ''A new era begins May 15th: My new single #NewEyes .''

When he announced 'Feel Something', Adam penned an open letter to fans which read: ''Let me offer a most sincere thank you for your patience and continued faith in me. You've pushed me to keep going even when I felt discouraged.

''I love making and performing music, but there have been many times where I've had to compromise on my artistic vision, with executives making decisions based on money and not art.

''Don't get me wrong--I'm VERY proud of my body of work. But I'm coming out of a dark period of second-guessing my own artistry and having my mental health suffer because of it. I started asking myself, 'Is all this hustle really worth it?'

''I put all my focus on work and started to feel detached in my personal life. My self worth was suffering, I was lonely, and becoming depressed.''

The former 'American Idol' star found performing with Queen gave him a much-needed boost but he also sought ''professional help'', as well as relying on the support of his loved ones.

He continued: ''Luckily, I have also been touring with Queen which recharges me with tons of positive energy. The fans we perform for are so full of love, and Brian May and Roger Taylor are a joy to play music with and always remind me of my value.

''Together we have collaborated creatively on our tours and this helped me to reaffirm my confidence in my artistry.

''Working with Queen helped keep my head above water, and I am so grateful to the spirit of Freddie Mercury, who has always inspired me to push ahead boldly.

''With a bit of professional help, and the support of colleagues, friends and family, I pulled myself out of the darkness.''

Adam went on to explain how he had ''reached out'' to new writers and artists, changed his management team and signed with a different record company and is now feeling much better about himself and his work.

He concluded: ''The tracks will chronicle the journey of taking responsibility for my own happiness and strength, and searching for intimacy. Since writing this song, I've found the joy I was missing and I'm back in my power. I can't wait for you to hear more!''