Does a DVD-writer use one laser for reading and writing?

vbimport

#1

Does a DVD-writer use one laser for reading and writing or one that does the reading and one that does the writing ?

Also does Lightscribe use a seperate laser ?


#2

For what I know, it is the same laser that performs reading and writing operations.

Each media type moreover has a separate laser, i.e. there is a laser for DVDs, a laser for CDs, and a separate laser for lightscribe functions :slight_smile:


#3

[QUOTE=geno888;2448314]
Each media type moreover has a separate laser, i.e. there is a laser for DVDs, a laser for CDs, and a separate laser for lightscribe functions :)[/QUOTE]
so you mean that i.e. a DVD-writer with Lightscribe uses ONE laser for reading/writing/lightscribing but that i.e. a DVD-writer without Lightscribe or a CD-writer also use only ONE laser but that that is a different type of laser right ?


#4

Sorry, I explained wrongly :flower:

I mean that on a lightscribe drive there are three separate lasers:

  1. a laser for read/write CD
  2. A laser for read/write DVD
  3. A laser to write the lightscribe surface on purposely manufactured discs.

The data surface of a lightscribe DVD is written by the same laser that writes on regular discs (the number 2 in my above example). In fact, the lightscribe label is not written on the data surface, but in the other face of the disc :slight_smile:

On a not-lightscribe burner there are only two lasers:

  1. a laser for read/write CD
  2. A laser for read/write DVD

#5

[QUOTE=geno888;2448325]Sorry, I explained wrongly :flower:
[/QUOTE]

and I misread your first line saying there’s only one laser for reading and writing :o

I understood : there’s only one laser in all (I must’ve been reading through my eye-hairs or so :P) so I didnt understand the rest of your reply and thats why I replied :slight_smile:

[QUOTE=geno888;2448325]
I mean that on a lightscribe drive there are three separate lasers:

  1. a laser for read/write CD
  2. A laser for read/write DVD
  3. A laser to write the lightscribe surface on purposely manufactured discs.

The data surface of a lightscribe DVD is written by the same laser that writes on regular discs (the number 2 in my above example). In fact, the lightscribe label is not written on the data surface, but in the other face of the disc :slight_smile:

On a not-lightscribe burner there are only two lasers:

  1. a laser for read/write CD
  2. A laser for read/write DVD
    [/QUOTE]

I fully understand it now. very clear explanation !

btw when I open my disc tray of my samsung SH-S222L I notice a faint glowing reddish light coming from a LED or so.
On my former SH-S2222A (non lightscribe) I don’t recall seeing this light. Can this be the Lightscribe laser showing a bit of visible light or so ?


#6

English is not my primary language, so sometimes my posts are not fully clear, sorry :flower:

[QUOTE=maicod;2448338]when I open my disc tray of my samsung SH-S222L I notice a faint glowing reddish light coming from a LED or so.
On my former SH-S2222A (non lightscribe) I don’t recall seeing this light. Can this be the Lightscribe laser showing a bit of visible light or so ?[/QUOTE]

Yes, that red thing is the lightscribe laser :bigsmile:


#7

[QUOTE=geno888;2448343]English is not my primary language, so sometimes my posts are not fully clear, sorry :flower:
[/QUOTE]

hehe no worries. its mine neither. mine is Dutch and yours is Italian I guess :slight_smile:

[QUOTE=geno888;2448343]
Yes, that red thing is the lightscribe laser :bigsmile:
[/QUOTE]

o funny that is emits any light. I thought infrared lasers never emitted visible light :slight_smile:


#8

Better avoid anyway to look directly at that laser :eek:

It could do some serious damage to eyes :doh:


#9

yeah I will be careful though I think its not using its writing power strength (its presumably idle) when the drive is idle and the tray is open


#10

Although I don’t have a drive that supports it, it sounds rather odd that an additional laser would be required for lightscribe. The same wavelength is used for writing to the lightscribe side as is used to write a burnable CD. (It is my understanding that discs are flipped after burning to create the lightscribe image).
Many drives come in versions that either support lightscribe or not, and as far as I understand the only difference is the firmware (since a per device royalty is presumably paid). Drive manufacturers would not be happy if they’d have to include a third semiconductor laser that would not and could not be used in most of the units sold.
Having a dedicated laser would only make sense if a device was made that could handle burning + lightscribe without the user having to flip the disk, and that would make the device far more complex since an additional mechanism would be required to move the laser assembly over the disk.


#11

you’re right !

excerpt from :

http://www.discmakers.com/duplicators/manual/LightScribeFAQ.asp#1

“Q: What is LightScribe?
A: LightScribe allows users to etch or burn an image into the top of special LightScribe-enabled media. It uses the same laser that burns content onto CDs & DVDs to also transfer black-shaded images onto the top of specially-designed LightScribe CD-R’s and DVD-R’s, combining both a burner and a printer into one drive”

This makes me wonder if it is true that a DVD-writer uses 2 lasers, one for CD-writing/reading and one for DVD-writing/reading as user Geno888 says ?

I think its getting time to open up an old DVD-writer to check :wink: (I ain’t got one though)


#12

[QUOTE=geno888;2448343]Yes, that red thing is the lightscribe laser :bigsmile:[/QUOTE]
There is no lightscribe laser. What you mean is just the led sensor used to read the bars at the center of the LS disks.
The drives use seperate lasers for CDs and DVDs because of the different wavelengths.


#13

oooops :o:o