Handtops, UMPC - LED Projectors by Mitsubishi, Samsung an

12/21/05 + AI

I posted a reply on the post link
But I thought it be appropriate to post it with a new title.

I have been keenly searching for Mitsubishi PocketProjector for the last six months and as most of us are perhaps aware that official release has also been postponed several times. From July to September, and now 19th Dec 2005. So I called up Mitsubishi and they regretted that it is still delayed.

Mitsubishi Taiwan Asia market is reporting 1Q 2006.
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Samsung is also releasing its LED based projector called Pocket Imager (model SP-P300MK), due to be released next month (January 2006)
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The Toshiba LED powered micro projector is out in France and it is to be released in UK around Christmas (or early New Year).
Find below the hyperlinks for detail perusal:
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The images on this link are detailed however I believe the description in the article quoting 400 ANSI lumens is a mistake. Verify it with product release info from toshiba France website.
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Those interested in checking out the projected images by Mitsubishi LED projector (model PK10 or PT10) and by Toshiba LED projector (model FF1) follow the links below:

More detail review and images with battery of Mitsubishi Pocketprojector at:
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Click the last image in the gallery at the bottom of the page to see the projected image by Mitsubishi PK10
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The projected image by Toshiba FF1 is shown in the penultimate image on the link below. The attached battery is also visible.
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The important question is ANSI Lumen and LUX values. Samsung states 23 ANSI Lumens while Mitsubishi and Toshiba indicates 250 and 400 LUX respectively.

Using the formula described on the following hyperkink:
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My calculations for producing a projected image of 70cm(W) by 50cm(H), approximately 83cm(33inches) diagonal view:

Mitsubishi probably has 102 ANSI Lumens (calculated) and 250 LUX(stated) compared to Samsung having 23 ANSI Lumens(stated) and 55.9LUX(calculated). Whereas Toshiba’s LED projector is rated 400 LUX (stated) and 165 ANSI Lumens(calculated). I could have miscalculated, so verify with the formula! Please note that resolution 800 X 600 is 4:3 ratio or (1.34) therefore I choose screen size 70cmX50cm, ratio (1.4).

All three projectors have SVGA (800X600)native resolution. Weight wise Mitsubishi is the lightest 450 gm (without battery) and Samsung is the heaviest 660gm(perhaps without batter). The Toshiba is 556gm (without battery)

In my assessment Toshiba LED Projector is perhaps the best of the three. I have ordered mine.

01/17/06 + AI

Good article, worth reading.
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01/17/06 + zzonbi

Yeah, but things don't look as bad as I thought, if that 38% value is an absolute maximal diference, considering the minimal perceivable step is in that neighbourhood too.

Funny, I thought of this very explanation the other day myself, for the sudden raise from 23lm to 25lm in some specs: 'Cranking the green-light output and dimming the other colors to gain brightness.' That seems particularly easy to implement in a LED model. It doesn't mean they actually did it, but hey, 'specmanship' is an art lol

In the end, I'd like to notice there is not such a thing as an ANSI lumen. A lumen is a lumen, it is very strictly defined already. The ANSI part, or whatever other co-name, refers to a practical measuring method, not the unit itself. It's an accepted language stretch, though (like SAE hp or DIN hp).

01/17/06 + zzonbi

Oh dear, my own example is not that clear, as DIN hp may actually reffer to a different unit too, than imperial bhp, conceived from rounder figures in the metric system.

01/29/06 + AI

Still waiting for the delivery of my order for Toshiba LED projector. It was expected on 30th Jan but received an email saying further delays in stock. Meanwhile I managed to discover some more images and a review in German language. The first link below is probably showing a projected by Mitsubishi PocketProjector.
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The following link is a review of Toshiba TDP-FF1 projector (Use a translation website). On the first line and in the second paragraph there is mention of 80 ANSI lumen.
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The images are quite clear to make judgement.

01/30/06 + AI

Here is Samsung Pocket Imager video review. Visit the following website:
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then click on www pcwelt tv link in the article.
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The review mentions 80 cd/m2 of brightness. I am not sure how to convert into lumen or lux for equal comparison.

01/30/06 + zzonbi

Apparently the same 'rule' reapplies. They now mention 81cm diagonal and 300lx. That gives 80lm.
They changed other figures too. Now the screen diagonal goes from 0.8 to 7.62m!? with an unchanged throw range, albeit uncertain. The angle of projection becomes very large now, not impossible but at least unusual.

As for the cd/m2, that unit is used for luminance (as from a CRT tube), not illuminance. It could give as much as 56lm though.

All in all, just more confusion.

01/30/06 + AI

Reviewing all theses hyperlinks several times, I am relying on subjective assessment based on projected images and visible ambient light in the still pictures/videos, because objective verification with lumen, lux or candela is becoming difficult without standardization.

From what I can notice Samsung’s projection is in a pitch darkroom with small image size, while Mitsubishi’s projection is in a dingy room but its image looks slightly better than Samsung in size. On the other hand, Toshiba’s overall package and clear presentation is obviously the best than the former two brands. Its projected images appear to be in a room with reduced ambient light and larger image sizes. There is projector control setup, high gain screen, remote control, USB pendrive compatibility and the included battery.

For the desired task, I feel it is the right choice at the moment.

01/31/06 + AI

Using the conversion calculator:
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80 cd/m2 is equal to 7.43225 Candela/ft2

Multiplying 7.43225 with 10.76 = 79.97101 Lux

I am not sure but that is what I have deduced from the following link.

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1 Lux = 1 lumen / sq-m
1 candela / sq-ft = 10.76 cd / sq-m

1 footcandle = 10.76 lumen / sq-m

If this is correct than Samsung’s stated 25 ANSI lumen is exaggerated.

01/31/06 + AI

May look unrealistic but if above conversion is correct than calculated lumen will be 3.64 based on 79.97101 Lux.

01/31/06 + zzonbi

The candela and lumen are different things. We shouldn't mismatch diagonals either when using luxes.
I guess the data in those articles is still rather unsure.
For the Samsung looks like they measured pointing to the screen, not the projector? For the Toshiba the diagonals they indicate are very different than all pdf data.
A luxmeter is cheap these days, like 30$.

01/31/06 + educationk12

I just want to make sure I am clear...there is no way this will project above 800x600 resolution, i.e. I can't do XGA, or SXGA...or...can it do it, but it'll just be pixelated or whatever the correct term.

Just wondering, I just feel the need to ask this again, because I'm not quite clear and if it did xga then I'd be more interested in it.

02/01/06 + AI

The native resolution of all three projectors is SVGA i.e. 800 X 600, however to my understanding they will accept signals from XGA input.

02/01/06 + AI

Toshiba Japan webiste has updated info.
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Brightness is 400 LUX for 11 inch image size and 15 lumen output

02/02/06 + educationk12

So nobody has gotten any of these yet...I guess when someone does then they will hopefully report on the higher resolution.

02/03/06 + AI

Mitsubishi PocketProjector 2nd preliminary Review:
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