[填空题]
Light of wavelength 590 nm passes throwzrll, 2w0c v7f /z 6h5a+hihzugh two narhfb39m9b1,uv5 yf* qa *ejfbmrow slits 0.60 mm apart. The screen is 1.70 m away. A second source of unknown wavelength produces its second-order fringe 1.33 mm closer to the central maximuv3f myqj,*9e f*fh 9 51bmbubam than the 590-nm light. What is the wavelength of the unknown light? $\lambda_2$ nm
