In the following tests, we examine the DVD reading capabilities of
the LiteOn SHW-1635S drive with scratched / defective
For the tests we used CDVD Benchmark and Nero CDSpeed. The reference test
- Single Layer media
This is a single sided, single layer DVD-ROM with 4.7GB capacity, and its
surface has an artificial scratch of dimensions varying from 0.4 to 3.0 mm.
The following transfer rate picture comes from the CDVD Benchmark v1.21 transfer
Excellent reading, with no drops in speed and the drive managed to reach its max reading speed of 16X.
This is also a single sided, single layer DVD-ROM of 4.7GB capacity. The
data structure of the disc is exactly the same as that of the TDR-821, with
the difference that there are no scratches on it but instead, defective areas
of dimensions ranging from 0.5 to 1.1 mm. There are also fingerprints sized
Typical reading graph for all LiteOn drives, where the reading speed drops at the beginning of the second defective area, while it managed to complete the test without any significant reading anomalies. Once again, all the way up to 16X.
- Dual Layer media
This is an 8.5GB dual layer, single sided DVD-ROM disc with artificial scratches
of dimensions ranging from 0.4 to 3.0mm, on both layers.
Excellent performance. Both layers were read without errors. Note here that due to the max supported reading speed for DL media, the drive maxed out at 8X.
This test disc is a single sided, dual layer DVD-ROM disc with a capacity
of 8.5GB. The only difference between the TDR-845 and the TDR-841 discs is
that the first includes
defective areas and fingerprints. The dimensions of the defective areas ranges
from 0.5 to 1.1 mm and the fingerprints are sized from 65 to 75 micrometers.
Last graph, and the hardest to read, with two layers and four defective areas (two on each layer) and the LiteOn 1635S did quick work of this test media, reading it flawlessly once again, with only a drop in reading speed reported near the beginning of the second defective area on both layers. Seems like the fingerprints present a minor obstacle for the drive. Other than that, we can say that we have a job well done.
The TDV-541 is a single sided, dual layer DVD-VIDEO disc, with a capacity
of 8.5GB. The disc is based on the TDV-540 series which is designed for inspection
and adjustment of DVD-VIDEO players. The disc checks the layer switch operation
from layer 0 to layer 1 and also includes test pictures and test signals for
DVD sound files. The current TDV-541 also checks the error correcting
capabilities of the drive and includes scratches from 0.4 to 3.0 mm.
Excellent performance with this test media. Not much else to point out here as the above graph speaks for itself.
TDV-545 disc is based on the TDV-540 series. It is a single sided, dual layer
DVD-VIDEO disc with a capacity of 8.5GB. The TDV-545 includes artificial black
dots on the data surface, sized from 0.4 to 1.0 mm. It also has 65 - 75
Once more, the drive showed its best when reading this media.
All the above tests indicate a very good error correction mechanism, with fingerprints being the only defect the 1635S has any problem with, if it can be considered that. The drive successfully completed all reading tests.