Why can I watch DVDs but not Blu-rays?
As a specialized manufacturer of portable entertainment devices, Aestiquo offers a high-quality video experience through its PD series DVD players. However, many customers have asked, "Why can't I play Blu-ray (BD) discs while DVDs can?" This article will explain in detail the physical structure and reading technology differences of optical discs, and explain why Aestiquo products are not BD compatible.
The Evolution of Optical Discs: The Leap from DVD to Blu-ray
The Digital Versatile Disc (DVD), which debuted in 1996, offered approximately seven times the data capacity of conventional CDs (4.7GB per side), greatly promoting the digitalization of movies. However, the Blu-ray Disc (BD), which debuted in 2006, surpassed this by achieving a capacity of 25GB per side (50GB for BD-50), and made it possible to record 4K resolution and high-resolution audio. This dramatic evolution was the result of dramatic improvements in laser wavelength and data recording density .
| specification | DVD | Blu-ray Disc (BD) |
|---|---|---|
| Data capacity (single side) | 4.7GB | 25GB (50GB for BD-50) |
| Laser wavelength | 650nm (red) | 405nm (blue) |
| Track Pitch | 0.74 μm | 0.32 μm |
| Video compression method | MPEG-2 | H.264/MPEG-4 AVC, HEVC (H.265) |
1. Differences in laser wavelength determine which discs can be read
DVD players use a 650nm red laser to read data, while Blu-ray players use a 405nm blue laser . The shorter the wavelength, the more accurately the laser can identify the tiny pits (information recording units) on the disc surface, allowing more data to be stored in the same area.
According to the optical disc standard of the Japan Electronics and Information Technology Industries Association (JEITA), this wavelength difference fundamentally cuts off disc compatibility ( JEITA Optical Disc Standard ).
The optical pickup of the Aestiquo PD series is designed exclusively for red lasers. It does not have a light-receiving element that can receive blue lasers or an objective lens that is tuned to the wavelength, so it is physically impossible to read BDs.
2. The structure of the data layer determines the recording capacity
Another major difference between DVD and BD is the track pitch (the distance between the grooves in which data is spirally arranged). The track pitch of DVD is 0.74 μm , while that of BD is 0.32 μm , which is about half the size.
Furthermore, the pit size on BD has been miniaturized to approximately 0.14 μm, which has resulted in a significant increase in data density per unit area.
Although it is clearly stated in the Aestiquo PD156 instruction manual, our products do not have a high-precision positioning mechanism that can read these minute tracks (Aestiquo PD156 Instruction Manual, Chapter 3).
Reasons why the Aestiquo PD series does not support BD: Hardware and software limitations
1. Physical limitations of optical pickups
The optical unit installed in the Aestiquo PD series is made up of parts specifically designed for DVD/CD. Because it does not have the blue laser diode or objective lens optimized for short wavelengths required for reading BD, the laser cannot recognize the pits on a BD disc, and the message "Disc not recognized" is displayed.
2. Decoder chip functionality limitations
Another major factor is the difference in video compression methods. DVDs are primarily compressed using the MPEG-2 method, while BDs use more advanced compression methods such as H.264/MPEG-4 AVC and HEVC (H.265) .
The Aestiquo PD series decoder chip only supports MPEG-2 and cannot process BD codecs.
3. Selection based on product design philosophy
Aestiquo 's PD series is a product lineup that emphasizes portability and low power consumption . BD drives require laser modules and cooling mechanisms, which increase power consumption and size.
To meet users' needs for "enjoying videos easily anywhere," we have optimized battery life and portability by eliminating BD functionality.
Frequently Asked Questions (Q&A)
Q1: Can I play BD-R (writable Blu-ray disc)?
A1: No. The reading principle of writable discs such as BD-R and BD-RE is the same as that of pre-pressed BDs. Aestiquo products do not have a blue laser, so they cannot play any type of BD.
Q2: Will a firmware update enable BD playback?
A2: Unfortunately, this is not possible. Blu-ray playback requires hardware (a blue laser unit and a high-performance decoder), and cannot be achieved by simply updating the software.
Q3: What should I do if I want to enjoy videos with higher quality than DVD?
A3: Please consider the Aestiquo projector series . Many models are equipped with HDMI inputs, so you can enjoy 4K content by connecting to a Blu-ray player or streaming device ( see Aestiquo projector product page ).
How to use Aestiquo DVD player optimally
The Aestiquo PD series offers high-quality playback of video and music files (MP3, MPEG-4, etc.) stored on DVDs, CDs, and USB flash drives. The PD156 in particular features a 180-degree rotatable display, making it easy to use in the car or while traveling.
Currently, the official website is running a special promotion for portable DVD players ( 便携式DVD播放器促销信息).
Optical disc technology has evolved dramatically, but each format has its own unique technical limitations. Aestiquo carefully balances functionality and portability to provide products tailored to your needs.
We will continue to expand our product lineup incorporating the latest technology, so please follow us on our official website and social media.
