If you've ever dreamed of having a battery-powered projector about the size and weight of your smartphone that could interface to your phone, tablet, or laptop, your dream has come true. Celluon is offering its new 1920x720 PicoPro laser projector at price of $349 on outlets such as Amazon. Illumination is provided by five lasers, and no focusing is needed regardless of projection size. This projector is not appropriate for classroom or boardroom presentations and is of limited use in bright rooms because it is rated at only 32 lumens although its contrast ratio is rated at 80,000:1. But there is anecdotal evidence, backed by some actual science, that the perceived brightness of the PicoPro is higher than its lumen rating (more on that later).

Prime applications for the PicoPro are one-on-one Powerpoint presentations and tutoring. Businessmen and teachers will appreciate the ease of slipping the PicoPro into their laptop case, briefcase, or shirt pocket knowing that they have several hours of projection time available before recharging the battery. The PicoPro can project on just about any surface, but a pop-up screen provides the best contrast, color saturation, and black level.

Lasers do a good job of projecting onto all sorts of surfaces, but those surfaces generate differing amounts of laser speckle. The PicoPro has a fairly soft focus to minimize this effect, but that cuts both ways: video and photo content looks terrific, but alphanumeric content is not sharp and clear. The takeaway here is that you won't want to use the PicoPro for a spreadsheet or document presentation unless the fonts are quite large. There are no image adjustments available on the PicoPro, but fortunately the factory settings are pretty good in terms of color balance and saturation. Besides, this is not a home theater product so some image compromises are expected.

The shirt pocket PicoPro is going to spawn a raft of applications unserved by current pico projectors. Its battery lasts for about two hours when wirelessly coupled to a Miracast or DNLA compatible device and for about three hours when directly connected to an HDMI or MHL compatible source. When you have access to an AC outlet, the supplied charger will recharge a depleted battery in a few hours and power the PicoPro during the charging cycle. In addition, a stand is supplied that cradles the PicoPro when used for an extended period.

When you match the image size to the ambient light conditions, the PicoPro puts up a vibrant, colorful image. Focus is a little soft which gives video a film-like quality, but that focus is retained regardless of how far the projector is from the projection surface. That surface can range from hallway walls to doors, sheets, ceilings, and traditional screens.

Thanks to the nature of laser light, there is little color shift due to the surface color, but the amount of laser speckle varies widely with surface smoothness and reflectivity. Metal surfaces produce the most speckle and traditional screens the least, but there is a simple solution to the speckle issue: sit slightly off-center from the PicoPro's centerline. Most of the speckle is reflected perpendicular to the projection surface, so sitting as little as 30° to the side reduces the speckle effect but does not impact perceived image brightness.

In our sample unit, there was a slight red emphasis to the image, but it was minor and skin tones were quite natural. Saturation was also a bit on the high side, but it served to give the image depth when it was affected by ambient light. One item that is adequate only in the quietest surroundings is the audio output. Even at full volume, it is quieter than a smartphone speaker, so it is desirable to attach an external speaker via the audio output port especially if the PicoPro is playing to an audience of more than one.

Everyone's tolerance for image quality varies, but our rough estimations of image diagonal for satisfactory image brightness, contrast, and black level are as follows:

Darkened room - 96"
Dimly lit room - 48"
Indirect sunlit room - 36"
Direct sunlit room - 24"

These diagonals were determined using a 1:1 gain pop-up screen, so the above estimates will decrease if projecting on surfaces like colored walls, painted brick, or bed sheets.

There is little to do when using the PicoPro other than charge the battery and connect wirelessly to your phone or tablet or connect via the supplied cables to your HML or HDMI source. iPhone users will have to purchase Apple's AV Lightning Digital Adapter to make a wired connection, but a wireless connection can be made via Miracast or DNLA. When the PicoPro powers up, it is ready in a few seconds to make a Miracast connection, but it can switch to DNLA or HDMI at the touch of a button. In our case, a Samsung Galaxy S4 Mini was put in Mirroring mode and immediately connected with the PicoPro using the Miracast protocol. Likewise, a direct HDMI connection was made to an HP laptop with no problems.

Although there are no image adjustments available, there is a unique, built-in calibration procedure if the lasers ever become misaligned. Horizontal and vertical positioning of each of the five lasers (two red, two green, and one blue) are provided. The process is a bit cumbersome, but alignment should not be required unless the PicoPro has been shocked significantly. Normal handling will not affect alignment, but a drop on pavement would warrant a look to make sure the lasers are still aligned. The good news is that you can do this alignment yourself without needing to return the PicoPro to the manufacturer.

A quick aside to the technologists in the audience. The PicoPro light engine is a Sony modification of the original MicroVision laser engine. Projection performance has been improved and battery life has been extended into the 2-3 hour range depending on connection format. Inside, five lasers are passed through a color combiner that focuses a single beam on a gimballed MEMS mirror. The mirror performs a raster scan which creates the image a pixel at a time. The process is so fast that no image flicker is discernable, and the engine runs cool enough that no fan is needed. This engine accounts for the PicoPro's small size and weight, but its low brightness is also by-product of its small volume.

In addition to the Powerpoint and tutoring applications mentioned earlier, here are a few possible locales for the PicoPro:

Dining. I recently showed a colleague photos that I took with my smartphone. We were at lunch and the image was projected on the tan-colored wall next to our table. The roughly 20" image was easy to see even with moderate ambient light although contrast and saturation were low.

Indoor sporting events. A coach could video a practice session on a smartphone and playback the important plays on a pop-up screen, the gym wall, or even the floor itself with varying image quality, but the image would be big enough for the whole team to see easily.

Camping. The family could enjoy a movie or scenes from a recent family event by tacking up a sheet and waiting for the sun to go down. An external speaker would be needed, but it would be an easy set-up even in rough conditions.

Just to keep things in perspective, the PicoPro is not bright enough for high ambient light or very large images, but it can handle most indoor environments and produce images much larger than the phone or tablet connected to it.

Constant Focus Convenience. The nature of the laser light engine keeps the projected image in focus no matter the distance you place the PicoPro from the projection surface.

Size and Weight. Competing 1280x720 pico projectors are 2-4 times the volume and 1.5-2.5 times the weight of the PicoPro. They hardly could be called shirt pocket projectors, but they do offer much higher brightness (200-300 lumens) than the PicoPro.

Input lag. With an input lag of 35ms, the PicoPro makes a pretty good personal projector for video gaming.

No Rainbow Artifacts. By virtue of its five-laser design, the PicoPro does not produce the rainbow artifacts that bother some viewers of DLP-based projector images.

Warranty. The PicoPro is warranted for one year.

Brightness. Our sample unit exactly met its brightness rating with a measurement of 32 lumens. However, as mentioned earlier, there may be evidence that perceived brightness might support a higher rating. Laser illumination systems are typically low in luminous flux (which is measured in lumens) but high in luminous intensity (which is measured in candela). There is no direct correlation between these two measurements, but anecdotal user feedback suggests that laser projection systems "look" about 50% brighter than their lumen rating. More research needs to be done on this phenomenon.

Brightness Uniformity. Uniformity was superb at approximately 96% -- as good as it gets.

Image Size and Offset. With a throw ratio of approximately 1.25:1, the Pico Pro puts up a 40" diagonal image from a projection distance of 48". But since the center of its projected image is on the centerline of the lens, the PicoPro needs to be placed in its stand or at the edge of the table or desk it is resting on so that the bottom of the image is visible. For example, at a projection distance of 48", the bottom of the image is nearly 8" below the centerline of the lens.

Fan Noise and Heat. There is no fan, so the PicoPro is totally silent. There is an internal thermal cutoff if ambient temperature gets too high, but this won't be an issue for most locations.

Low brightness. At 32 lumens, the PicoPro has the lowest brightness of other pico projectors of its resolution. Perceived brightness may be somewhat higher, but it is still inadequate for high ambient light conditions.

No image adjustments. The PicoPro is designed to put up an attractive image at a low cost in a small, light package. One of the tradeoffs for those design criteria is an absence of user controls. Fortunately, the video image quality is very good, so for many users, this won't be a serious limitation.

Poor data quality. Inherent design considerations keep the PicoPro from delivering crisp alphanumeric images. Spreadsheet and document presentations only work effectively if type fonts are large.

No keystone correction. The PicoPro must be orthogonal to the projection surface in order to square up the image, so projecting above eye level can be problematic.

The Celluon PicoPro breaks new ground in terms of portability coupled with long battery life and high resolution. It is perfect for small groups, and while it does not offer a home theater experience, it does a good enough job that family gatherings and casual business meetings do not suffer. High ambient light is the PicoPro's nemesis, but if shades can be drawn or darkness falls and image size is not too large, video quality is very good, and the price is right.

For more detailed specifications and connections, check out our Celluon PicoPro projector page.

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