new Brand of Hologram Laser (LDGU) LT0H30PA inside by Philips CDM12 and VAM12 mech
Dear Mr. smartech, hello everybody
I would need for service by a instrument for non-contact thickness measurement of transparent plates the currently manufacturer of the following hologram laser diodes, formerly manufactured by Sharp :
1) LTOH30PA (LT0H30PA), TO-outline
2) GH6C005B3B, outline: "Compact Resin", CD-RW compatible version
by first is a datasheet online,
by the second, unfortunately not. For the CDR-compatible former type, inside by Philips CDM9 (CDM-9) there are data sheet online again, (see also patent US5511059), keyword "LTOH12M" by Google, see
Sharp let me know, that all types of hologram out of production , but unfortunately don't let me know about the new brand. that must have taken over the whole hologram laser diode range. By search on the web I don't find the right informations. Here the quotation of the the reply from Sharp manufacture in Japan to Sharp agency in Hamburg Germany:
To begin with the conclusion, we can never support the below models.
Although I am NOT sure whether its discontinuation procedure is certainly implemented,
Production is obsolete and those alternatives are nothing, Sharp is not promoting Hologram laser any longer.
Is “Tiefbassuebertragung” a company spinout from Philips, Thomson or something who used to use these models?
If so, please be careful and investigate the history with them, so that our discontinuation situation will not be big problem (complaint for discontinuation).
But there are nothing advices about new brand.
The above mentioned hologram laser diodes are inside in all
CDM12 (CDM-12) and VAM / VAU 12/22xx versions from daisy laser (formerly Philips), even in the currently available professional versions, as shown in the schematic of the data sheets, e.g. VAM1254 - as you can see by
http://www.akustik-perfekt.homepage....au1254bis1.pdf - VAU1254/11 Aug 2000
(Application Note Daisylaser VAU1254-31LF ANVAU12540601)
http://www.daisy-laser.com/products/...fVAMspec11.pdf (VAM1254/21, Nov 2003 page 23)
www.vendoramusements.com/images/DataSheet.pdf (VAM1254/01 August 2000)
http://www.daisy-laser.com/downloads...s/prem7000.pdf (CD System "Premium 7000" )
Furthermore, this types are inside by Sharp optical pick up HPC1LX ", as the cd player service.manual from Kenwood DPF1030/2030 shows, also as download PDF by http://www.rc5.ru/upload/Kenwood_DPF-1010,2010.pdf
Thank you for your advices about today's name of brand.
Please excuse my not perfect english (I work with language tool by google) but I hope, you can understand the most.
all the best and greetings to California
Really nobody knows about this?
Members whose native language is Japanese or Chinese, should find out this one very easy. By the forum "cndiyclup" you can find a wide range of information - see
Another source for this information there are the manufactures in Japan and China, e. g.
All brands uses succession model from Sharp's HOLOGRAM LTOH30PA by their CDM12 optical pick up Philips clones and they must be necessarily buy by particular semiconductor manufacturer. The currently name or webaddress of this brand I need.
I've even tried to ask there, but I always misunderstood. Unfortunately, both my English as that of the employers there is not enough.
by this forum I get the wanted information - so I think:
Good to see by the CDM/VAM photos is the TO-outline at solder site of the hologram laser diode successor LTOH30PA (LT0H30PA), that must comes now from other brand than Sharp.
Perhaps one of the diyaudio members from China can read there and posting the informations here - thank you very much
also this supplier for diy compact disc player could have informations:
an additional thread from China with fine images of diy cd player and several informations:
Where are all the diyaudio members from China?
LTOH30PA (LT0H30PA) I still want to know the currently manufacturer of this hologram laser diode, used in optical pickap's from the daisylaser transport CDM12 and VAM1254/CDproLF-II
are there still not news?
about the URL
I read about post Published on: Sun 12 Yue 21, 2008 5:09 pm follow:
For personal point of view, ordinary CDM12.1 with VAM1201 or VAM1202 very similar, and the performance is very similar, but VAM1202 better.
However, the general products and professional goods, there are still big differences, so the ordinary VAM1201 with VAM1254 things are not the same level, always exist in nature is different.
For a laser head, the decision performance and reliability of the most important part is laser tube, Photodetector (Optical test tube) and Actuator (ie coil), of course, small enough to glue in a design of laser head Similarly, there are very important. For example, Pickup body, generally the stability of aluminum-magnesium alloy for high, and PHILIPS in this area of plastic injection technique quite amazing reliability is also quite good.
For the previously mentioned was the greatest difference between these bald, I believe that it is laser tube. For an ordinary laser head, the laser tube parts in the reliability and stability are the ordinary level of control. From the PHILIPS's CDM12.1 to CDM12.10, as well as the CD12i to VAM1254, the laser tube has a very different, although from the look and pins are the same there is not much difference. However, in the ordinary CDM12.1 above the fluorescent tubes, with its performance time is about 1000 hours, while the CDpro series of fluorescent tubes are often more than 5000 hours of specially selected products, and even special applications, however, the light tube, the SPEC more than 10000 hours. (For the definition of the time I do not know how ray tube plant concrete testing and the definition and selection)
For PHILIPS of the CDM, VAM series laser head, used in SHARP are provided by the holographic laser tube, the performance difference between the simple models that use different. In fact, these holographic laser tube is a precision component manufacturers are Panasonic and Sharp common two, to Sharp as a strong and widely used, followed by a large number of popular PHILIPS not unrelated.
For such precision components, their internal LaserDiode and Photodetector for Bonding installation rather strict distinction between different types of crystals in the Die already during a tight definition and selection of a preliminary decision has had this system price and performance, coupled with the accuracy level of processing technology and eventually produce different levels to the laser tube. For example, these LQH31 series of laser tube, the final machining process on the fluorescent tubes when the holographic lens in the split-focus and the internal installation of the ladder-shaped laser Die and adjust PD Die processing (conditional friend may wish to disassemble one to see, but it would want to see clear internal structure, 100X microscope is needed, but the focus is on crack for observe the holographic lens on the specific mode, 10x magnifying glass is sufficient). The adjustment of the processing requirements of very strict and will eventually affect the entire performance of the laser head (such as ABCD and EF balanced output, in fact the LQH31, 32 series of fluorescent tubes with ordinary shaved head on the four quadrant PD there are different, the output is only five rather than six).
The precise alignment process immediately after the completion of light-cured resin for processing (glue are used in special professional glue, performance requirements for high and processing is very expensive, the world's few suppliers, most of Japanese plants), while the levels of the different requirements of the laser tube and laser head, using different levels of glue, of course, the cost of the above is somewhat different.
A good laser tube and an ordinary laser tube processing can have more than ten-fold difference. Of course, different prices, suppliers to ensure performance standards are also 10 different.
It is such a difference in the differences in details, would create a different CDM and the Pro series, even if the final product, for the end-user the face of it, in the playback performance of the above difference was not significant, but in terms of reliability, stability, and the discrete nature of the above there is considerable difference between these different indicators, for the radio, or CD production lines for industrial applications depend on the parameters for the Dudie body, but it is very important.
The same reason, in other parts of the above, some of the optimization and refinement of difference, creating two different products.
The pursuit of the ultimate and highest performance of the Pro product, the highest mechanical stability of the metal frame, for Dudie body stability (especially for heat problems and weather resistance) are also purposeful use of land. This bald-headed with ordinary plastic frame also has a large difference (of course, plastics, mechanical stability of the contrast to the daily life of the plastic is unusual, but compared to the high stability of metal still has the distance.)
In addition, for the choice of IC products, small to ordinary resistors, for the Pro Series, the adoption is not an ordinary chip resistors, the noise and stability are also purposefully selected before.
Particularly for the bottom line is that I know, Pro inside the DSP are different from ordinary versions of the IC, the same as for the SAA7324H (CD10-I), but in different versions have very different, especially in some versions, but still there is not accepted by Bug (on CDRW testing can be distinguished by some of the indicators, I have seen a company PHILIPS have been returned Reject hundreds of thousands of Pcs, PHILIPS Kusi, it was about 7 years ago that time had just come out shortly CD10 I was there present, I also understand that some CD10 SAA7324 presence Bug, or even CD10-II SAA7326 There are also some versions of the same Bug, PHILIPS 1 million have been destroyed on the SAA7326 it, I have something I can confirm that to deal with this groups of people have just destroyed one of my good friends).
For Pro use DSP, are affirmed in a specific version, it be possible to guarantee that the professional performance of the final product.
Chit-Chat the above so much, but the performance is not the final product is very good very good? Very special?
--- No, the Pro does not seem to get CDM12.1 much better than ordinary, and even seemed to appreciate some of it is even worse than ordinary.
We may all have to see the Pro Datesheet inside the indicators do not outstanding in the actual tests such as the black spots ah ah fingerprints without scratching the performance of black belt red tape ah do not gnaw way, are very conservative general information. --- Does this mean that the Pro performance is not good enough? Lie?
Not, in fact, the key is a system designed to balance and stability, that is reliability, which is CDpro needs. Of course, CDpro performance will never be, under ordinary CD player, which, after all, is a high demand for the market, and thus its performance is below the average performance shown --- are slowly The so-called "proof of the pudding" time allows us to slowly come to see their performance.
This is also the same as the previous CDM4, which is a good example.
Is the so-called "lay watch the fun, professional and subtle" - only to understand, can we go to an objective assessment of what is good and what is bad.
For ordinary consumers, VAM1202 enough, after all, this is already worthy of paying too silver. What Chuimao while seeking fart (defect) in people, VAM1250 (for professsornal) may be sufficient, of course, we can continue to choose a higher VAM1254 (for Hi-End). Even VAU1254, after all, we do not have that kind of technology, because we are not engaged in skinhead study, we did not create so good. . . .
and about post Published on: Sun 12 Yue 21, 2008 5:33 pm follow:
In fact, the CD12 and CDpro inside PHILIPS use of two different packages of holographic laser tube.
One is the extensive use of CDM9, CDM12.x, CDM12, and CDpro laser tube inside a metal circle. That is below this figure.
Another is to use the CDM22x series and CDpro2 holographic laser tube inside the flat. That is, below the
Is very simple, technology is certainly moving forward, of course, the objective of technology at the lowest cost is to achieve the best performance, that is, at a reasonable cost under a reasonable performance, that is OK as stated in Cost-Down. ....
That is why today's laser head compared with the previous old bald at a much lower cost, process costs lower than the old products .... naturally there would be no reason for the less sophisticated of the.
Contrast to the kind of metal tube before the Pro holographic laser tube, and now the laser tube are basically resin-oriented, and even the lens is.
Gold-plated metal tube inside the already high cost of, plus what gold bongding line, the cost is not a lot higher ---- technological improvements is the use of low-cost things that make a good enough performance out of the tube. GH6C005B3 is indeed a the cost down a lot of product ... can see it used in a number of inexpensive products above ....
LT0H30PA is used in CDpro VAM1252 on.
GH6C005B3 is used in CDpro2LF VAM1254 on.
Literally understood, LF is LongLife ....... In other words, this GH6C tube in the face of long-life design .... significantly improved.
Another point is, GH6C it is the original based on the improved power performance, because access to post-CD era, more disc is CDR, CDRW disc, must be called for greater optical power and switch. Therefore, I believe is a response to this GH6C The raw bar ........
Another reason is the design of a new generation of bald, that is, the trend is consumer demand for sex-oriented thin, lightweight, low-cost-based system design, is bound to the structure of laser tube request, GH6C series of laser tube is similarly developed in response to this trend ....
Less for more and more of the design, performance, and is no longer good, then one may be unable to maintain a reasonable profit margin, then the final result is to improve or stop the production, use low-cost, high-performance products to replace .... ...
and about post Published on: Sun 12 Yue 21, 2008 5:39 pm the follow:
Invoking section 22 of House bbp published on 2007-07-23 11:18:
LTOH30PA and two kinds of laser tube GH6C005B should not just be the difference between round and flat and what is the deeper reason, LAOKUO brother to continue
Flat-type current is 36mA, a circular current of 55mA.
Unfortunately I don't find the way to open the image files and also not the currently manufacturer of this diodes. Perhaps a member from Taiwan can writen this question by the above mentioned forum - thank you very much
By the way - very fine impressions regarded DIY high end audio cd payers you will find after scroll down by the above mentioned URL
Too much is lost in translation I think...
from old stock I have found (unfortunately only) four pieces of VAM1202 heads where TO Sharp Hologram was in use. I remove this and replace the faulty version of some CDM12.4 with it. But now I need additional hologram diodes.
Therefore the same question again:
are there any news concerning currently manufacturers of hologram successors with same outline than Sharp's LDGU's "LT0H30PA"?
for more pictures of the old hologram laserdiodes from Sharp go to
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