蓝光：
蓝光可能是一种高清存储设备，与不同的光存储设备相比，它可能拥有更大的存储空间。它主要设计用于存储高清视频，而这在以前的 DVD 技术中是不可行的。与不同的磁盘格式相比，蓝光将存储大量信息，因此其背后的原因可能是磁盘上的信息层与光学设备之间的间隙较小。
由于将光学设备更靠近磁盘，它会产生更紧密的聚焦，更少的失真与较小的凹坑(和轨道)相关联。存储蓝光的最大空间是一个方面 25 GB。蓝光名称源于添加蓝色和光学“光线”，这是因为它使用蓝紫色光学器件而不是红色光学器件。因为蓝色激光的波长更短，有助于实现更高的位密度。
DVD：
DVD 代表Digital Versatile Disk，为磁带录音机(Video container Recorder)中使用的录像带和计算机中使用的固定存储提供了另一种形式，因为与 CD 相比，视频光盘将获得 7 倍的信息量。
它以出色的图像质量和随机访问呈现视频。视频光盘由类似的材料构成，因为 CD 但是方法和因此层区域单元完全不同，它从每个边缘使用，就像 2 个 CD 区域单元沿投影。在 DVD 中，使用 RS-PC 和 EFMplus 作为纠错码。
让我们看看黑白 DVD 和蓝光的区别：
| S.NO |
Blu-ray |
DVD |
|---|---|---|
| 1. | The single layer size of Blu-ray is 25 GB. | While the single layer size of DVD is 4.7 GB. |
| 2. | In Blu-ray, the recording or metal layer is situated closer to the reading mechanism’s objective lens. | While in DVD, the recording or metal layer is situated in middle of disk. |
| 3. | There are double layers of pits in blu-ray. | While there are also double layers of pits in DVD. |
| 4. | In blu-ray, there is 0.30 micrometer space between the spiral’s loops. | While in DVD, there is 0.74 micrometer space between the spiral’s loops. |
| 5. | It holds the 0.15 micrometer space between the pits. | While it holds the 0.4 micrometer space between the pits. |
| 6. | In blu-ray, picket code is used as the correction code. | While In DVD, RS-PC and EFMplus are used as the error correction codes. |
| 7. | In Blu-ray, the wavelength of laser in 405 nm. | While in DVD, the wavelength of laser is 650 nm. |
| 8. | In Blu-ray, the data transfer rate is 36 Mb/sec. | While in DVD, the data transfer rate is 11 Mb/sec. |
| 9. | The double layer size of Blu-ray is 50 GB. | While the double layer size of DVD is 8.5 GB. |
| 10. | The numeric aperture of blu-ray is 0.8. | While the numeric aperture of DVD is 0.6. |
| 11. | The thickness of blu-ray is 1.1 mm. | While the thickness of DVD is 0.6 mm. |
| 12. | It is used for storing large size data like shooting videos. | It is used for storing small size data like movies after release. |
| 13. | The cost of Blu-ray disc is high in comparison to DVD. | The cost of DVD is lower than Blu-ray disc. |
| 14. | The available video codecs of Blu-ray disc are MPEG-2, MPEG-4 and SMPTE VC-1. | The available video codecs of DVD is MPEG-2. |