A review of the LP-WU3500 from AV Views Germany

Hitachi LED Series

Today, our demands and expectations from professional projectors are more than just a high light output and good resolution. The processing speed must also be fast, with fully integrated, multiple connectivity options for all common signals is essential. While a good zoom lens with horizontal and vertical lens shift ensures a problem-free adjustment of the image position.

At ISE 2017, Hitachi launched their first projector with the new SSL engine. The LP-WU3500 utilises light-emitting diodes for a light output of 3500 lumens, the green light is produced by means of a yellow phosphorus rod, which Hitachi stimulates with blue light-emitting diodes. This technology is called HLD (High Lumen Density). We decided to take a closer look at the LP-WU3500 projector from Hitachi which has an image resolution of 1920 x 1200 pixels.

Hitachi: LP-WU3500

Hitachi has long been a firm favourite among the AV industry of professional projectors, as their wide range includes both LCD-based devices and DLP technology. During ISE 2017, a powerful DLP projector was showcased, which generates a light output of 3500 lumens from a light source based on LEDs. However, technical intervention is needed to achieve this, as green light-emitting diodes does not provide sufficient light output. Hitachi has therefore developed HLD technology in which the green light element, which supplies most of the light output, is produced by converting the light from blue LEDs using a phosphorus rod.

The outer dimensions and the housing shape are typical for a professional device. Although, somewhat unusual for this device category is that the projection lens is not centred. Nevertheless, Hitachi's delicately constructed horizontal and vertical lens shift capability allows for the desired image position to be optimized. A unique feature that we have never seen before, is that the zoom lens, which can be manually adjusted or locked using a locking screw, avoiding the displacement of projection.

The rear connection panel provides access for analogue and digital signals. This projector can be connected to a network via a LAN socket, or alternatively a USB socket is also available for a WLAN dongle. Additional digital connections are also located on the side of the projector including an HDBaseT socket for a digital signal, which must be routed over a longer power path. In addition, there is an HDMI input with MHL and an HDMI output.

We connect our picture signal to the projector and begin to power it up. Less than ten seconds later we are pampered by a picture in the best colour quality. A clean “yellow” illuminates us as well as a bright “red”. All colour transitions to the pastel shades are beautifully graded. This is a result of a 1-chip DLP projector.

Unfortunately, the picture quality changes when the light output is switched to “high”. Then, the green light component is disproportionately increased, which has a compromising influence on the light output. As a result, the “red” and “blue” colours appear too dark which also means that the “yellow” is hardly recognisable. In this context, you have to know that “yellow” is created by a mixture of “red” and “green”. If there is too little “red”, “yellow” changes to “green”.

We then measured the setting for maximum light output and we were delighted with the result. Our test device achieves nearly 4000 lumens instead of the expected 3500 lumens! That is an incredible 14% above the target.

Since the LP-WU3500 operates without the usual colour wheel, it means that no clear/white segment can distort the colour. We are convinced that much more is possible here. You can, of course, also take the IR remote control in your hand, and fine-tune the colours through the "advanced menu".

The IR remote control can also be connected to the projector via cables and can be used, to make a complex adjustment of the image geometry. Thus, not only a projection at oblique angles is possible, but also on curved surfaces. It is also feasible to overlap images with several projectors using the edge blending adjustments. Finally, it is noted that due to the powerful semiconductor light source, this enables the projector to project from any position, with 24/7 operation.

The LP-WU3500 from Hitachi is a high brightness DLP projector with WUXGA resolution, with an innovative light source allowing for a maintenance-free continuous operation. The projector warranty is 20,000 hours, or 5 years, whichever comes first. The colour quality is excellent and can be adjusted over a wide area. Our test device produced a much higher light output than expected.