Imanishi: “Sony has decided to exhibit a
2005-inch Laser Dream Theater at the Aichi
Expo 2005––.” We laser diode and optical
device engineers were first told of this plan
by Naoya Eguchi (currently General Manager,
Photonics Development Dept., Core Device
Development Group, Sony Corporation), who
was placed in charge of the video technology
for that theater, after the 2003 company internal research results presentation meeting. “A 2005-inch display? Is that even
possible?” When we asked this, Eguchi
replied “I don't know. But we don't have any
choice other than to create it.”
Naganuma: It was because there was the goal
of the exposition that the development project
had so much vigor and momentum.
Imanishi: Ms. Naganuma was originally a Blu-ray
Disc playback blue-violet laser engineer,
and I was also involved in a completely
different area. The group was assembled
by Shoji Hirata, the general manager of
the Advanced Light Technology Dept., to
develop a red laser diode, a device which
did not previously exist, in preparation for the
exposition. Although there were only a few
changes relative to the earlier technology in
the crystal growth technology that I was in
charge of, Ms. Naganuma, who was in charge
of mounting, had a much more difficult time.
Naganuma: Compared to providing a single
emitter in an optical disc playback laser,
the know-how required for assembling the
25 emitters used to achieve high power
was completely different. Since we had to
develop equipment in parallel with creating
prototypes, we spent all our time solving
problems. There were no days, including
Saturdays and Sundays, that we didn’t have
meetings with the equipment manufacturer.
Imanishi: Sony has technological advantages
related to red laser diodes. Sony was the
first in the industry to demonstrate red laser
diode operation, and we also had a proven
track record in the high power area with our
products for laser machining technology in
the automobile industry. Our approach was
to combine these while at the same time
meeting the new challenges. The “two-step
mounting” technique (see the illustration) that Ms. Naganuma and the others working
on mounting set out to achieve was just such
an effort, and in my group as well, we were
able to achieve previously unachievable
characteristics by attempting to use materials
that people told us couldn't be used.
Naganuma: Since a lot of weight was placed on
solving problems in the mounting area before
the exposition, I have a debt of gratitude to
Imanishi that I would like to repay.
Imanishi: We were able to work our way up
with alternating steps: when the crystal growth
issues we were working on were under control,
we'd work on resolving issues of concern
in the mounting area, and when those were
under control, we'd go back to crystal growth.
Recently, since there have been extremely
strong desires to use a new light source among
people working on projector development, we
must, I think, respond to those. We’d like to
create, as soon as possible, extremely large
displays for home use. This is because this red
is so bright and clear that users will truly be
surprised. While it goes without saying that we
must provide not only red, but matching blue
and green laser diode technologies, the Laser
Dream Theater has already shown that this is
possible technologically.
Naganuma: The reaction to the August 2008
press release was huge, and at the applied
physics annual meeting in Nagoya just after
that, in September, the poster session was well
attended even though it was the first session in
the morning.
Imanishi: People were overflowing into the
next booth: it was embarrassing. Come to think
of it, I passed by the site of the 2005 Expo
on the way to the conference, but the Laser
Dream Theater had reverted to its original use
as an ice skating rink and the places where the
other pavilions had been had become parking
lots. Three years ago, I took my family to the Laser Dream Theater, and was very pleased
that I had been able to help in creating such
wonderful images. Ms. Naganuma, did you go
to the exposition?
Naganuma: Yes. I also liked the frozen
mammoth that was on display next to the
theater. |
Vol.55