LB meaning in Physics Related ?

"Laser Beam" (レーザービーム, "Laser Beam") is a song recorded by the Japanese girl group Perfume for their third studio album, JPN (2011). It was written, composed, arranged, and produced by Japanese musician and Capsule member Yasutaka Nakata. The single also included the A-side track "Kasuka na Kaori", which appeared on the parent album. Originally scheduled for an April 20, 2011 release, it was postponed due to the 2011 Tōhoku earthquake and tsunami disaster. As a result, they both premiered on May 18, 2011 as the fourth single from the album in Japan. Musically, "Laser Beam" is an electronic song, influenced by 8-bit music.

Upon its release, the track garnered positive reviews from music critics. Some critics highlighted the song as one of Perfume's best singles from their album, and commended the composition. It was also successful in Japan, peaking at number two on the Oricon Singles Chart and Billboard's Japan Hot 100 chart. It was certified gold by the Recording Industry Association of Japan (RIAJ) for physical shipments of 100,000 units. An accompanying music video was shot by Kazuaki Seki; it features the girls performing the song in a futuristic labyrinth, trying to retrieve a suitcase by a mysterious man. It was performed on the group's 2011 JPN concert tour.