How should schools, tutoring centers, businesses, or individuals choose a projector? Here are some suggestions we've compiled to help you select the most suitable projector.
The two main chip technologies for projectors today are LCD and DLP.
LCD has more accurate colors because it uses three separate LCD panels for RGB, resulting in less distortion. This segment is primarily dominated by EPSON, which is also the largest supplier of LCD cores.
DLP is a technology from Texas Instruments (TI) that uses a single chip with many tiny mirrors to reflect different color segments from a color wheel very precisely in one second. Thus, its colors may not be as vibrant as those produced by three-color LCD technology, which is why some people feel that LCD projectors have more vivid colors.
DLP projectors are smaller because they use a color wheel, while most compact projectors are based on DLP technology. Additionally, because DLP reflects light rather than directly shining strong light onto the LCD color panels, its durability is significantly better than that of LCD projectors, making DLP projectors generally last longer than LCD projectors.
We recommend: For vibrant colors, use LCD; for longevity, use DLP.
Many large theaters have recently adopted "digital laser projection," indicating better image presentation. In fact, laser projection and lighting applications are quietly replacing traditional bulbs, sweeping the entire projector and automotive lighting market.
Previously, the most troublesome aspect of using projectors was the diminishing performance of bulbs. When it came time to use a projector, one had to quickly turn off the lights and close the curtains. Although LED (light-emitting diode) light sources appeared, their efficiency was also low. Laser (Laser Diode, abbreviated as LD), while having advantages such as collimation and focused light sources, has excessively high power and is not suitable for general light source use. Improper use could also cause harm.
The key advantages of laser light source technology are that laser light has high light efficiency under physical conditions and benefits from being focus-free, making it extremely convenient for personal use. Laser light sources also have a compact design, allowing them to modulate the projected color of light, simplifying the optical lens system that LEDs require, significantly reducing costs and space issues in optical materials. This also aligns with the micro-projection light machine's design direction of "miniaturization."
In recent years, the introduction of lasers has not only completely resolved various "chronic diseases" of projection but has also brought more possibilities to projection applications. Therefore, lasers have become the absolute core of projection technology, with manufacturers enthusiastically engaging in laser research and development. The maturity of laser technology has also elevated the projection industry to new heights.
Lasers have the characteristic of instant on/off, and during projector sleep, brightness can automatically be reduced, achieving energy savings of up to 90%. They can also automatically adjust brightness according to environmental light, which is difficult to achieve with traditional projectors.
Currently, the drawback of laser projectors is their high price; they have similar brightness to traditional projectors but cost seven to eight times more, discouraging many users from considering new light source projections.
Some manufacturers refer to laser projectors as "laser TVs," but the imaging principles of projectors and TVs differ. Teacher Mantou believes this term can mislead consumers, but it is a clever marketing gimmick.
We recommend: Laser light sources are the future trend—great but costly; if your budget allows, go for a laser light source!
The key advantage of LED light source applications is low cost! The design of LED micro-projection light sources in consumer electronics often impacts whether users adopt the design scheme due to cost limitations. As the cost of LEDs is relatively low, LED micro-projection light source designs continue to penetrate the market. However, even with extremely low costs, LED micro-projection light sources require optical lenses for processing light type, and users must adjust focus during projection, slightly increasing operational complexity. Nevertheless, the overall module cost of LED micro-projection light sources remains lower compared to laser micro-projection light source solutions, making end-user 3C product designs favor integrating low-cost LED micro-projection light source modules.
We recommend: If you're buying now, choose LED light sources to avoid losses; however, if you have a deep pocket, remember to go straight for a laser light source.
In the past, it was common to hear someone say a bulb is "so many watts (W)," with higher numbers indicating greater brightness. However, watts (W) represent the power of a standard bulb, and higher wattage consumes more electricity. Lumens are the unit of luminous flux, referring to the power of light; under the same distance, higher lumens mean greater brightness. Conversely, for the same lumen level, shorter projection distances yield brighter images; larger images require higher lumen levels. However, it should be noted that overly bright screens can harm the eyes when viewed for long periods.
ANSI Lumens is a brightness unit defined by the American National Standards Institute (ANSI) and can be used to measure the total light output of a projector. The calculation involves placing the projector 2.4 meters away and dividing the image into nine segments, measuring the brightness of the nine points on the white screen, and finally averaging them to obtain ANSI Lumens.
ANSI is a non-profit private organization established in 1918, currently composed of nearly a thousand member companies, academic and research institutions, trade associations, standards organizations, government agencies, and consumer and labor representative groups, responsible for coordinating domestic standardization affairs and promoting American standards in the international community.
LED lumens are often used by manufacturers to quantify the perceived additional brightness due to high saturation colors (Helmholtz–Kohlrausch Effect). LED lumens are not an industry-recognized brightness standard.
Light output brightness, or light source brightness, is directly measured from the light source (i.e., the bulb) without any modifications.
In summary, ANSI Lumens has become the primary standard for measuring projector brightness and is currently the only widely recognized standard by international organizations, thus possessing a certain level of trust and reliability.
We recommend: When discussing projector brightness, always prioritize ANSI Lumens as the main consideration; the higher the ANSI Lumens, the better!
Before choosing a projector, tutoring centers need to confirm whether they will be using the projector with the lights off or on during classes, then determine if the lumens need to be high or low. We recommend selecting projectors with over 3,000 lumens, as this allows the lights to be on during class. If the lumens are insufficient, the lights must be turned off for classes, which is not suitable considering the current teaching methods in tutoring centers.
Additionally, larger classrooms require higher lumen levels as the distance between seats and the screen increases. Factors such as windows, curtain walls, window size, direct sunlight, west-facing exposure, and reflections must also be considered. If these conditions exist, brightness must be increased, especially if students need to read printed materials or take notes; thus, keeping the lights on is necessary.
However, higher lumens can also have drawbacks, such as reflection and brightness issues. High-lumen exposure can cause students to feel dazzled, leading to eye fatigue.
We recommend: For home projectors, curtains can be closed, so lumens are less critical; for commercial use (business, school, or tutoring), lumens must exceed 3,000, with higher lumens needed in larger spaces.
When selecting a TV, computer monitor, or projector, the "contrast" value is frequently noted. Contrast is measured by instruments and is the ratio of brightness between the darkest static image and the brightest static image; higher contrast results in more saturated colors and sharper images.
However, some products label "dynamic contrast," which refers to lowering black brightness during dark scenes, maximizing the instantaneous black-and-white contrast. The dynamic contrast values obtained are often 3 to 5 times higher than static contrast values. Therefore, when choosing a projector, careful consideration of the intended use is essential.
We recommend: The higher the contrast, the better!
The focal length of a projector relates to the projection distance and the size of the projection screen. Projectors with longer focal lengths require longer projection distances but can project larger images. Short-throw projectors can project large images from short distances, suitable for confined spaces.
In larger spaces like conference rooms or living rooms, the projection distance is generally less restricted. However, it is still essential to pay attention to zoom distances; if the distance is too far and the focal length is too short, it can adversely affect image quality due to oversizing.
In smaller rooms, such as bedrooms or small apartments, the projection distance is limited, so it is advisable to choose a short-throw projector if the budget allows.
Higher-end projectors often feature a large zoom focal length design, enabling them to project a specified image size regardless of whether they are positioned closer or farther away, giving users more flexibility in choosing projector installation locations.
We recommend: Measuring the projection distance (the distance between the projector and the screen) is crucial!
When purchasing projectors for tutoring centers, it is essential to consider not only the projector's price but also the lifespan and cost of the bulbs.
The pricing of projector bulbs usually exceeds tens of thousands, and generally, they can last for at least 1,500 hours or even 3,000 hours (please refer to the projector's manufacturer's data). If a tutoring center uses the projector for about 30 hours a week, that amounts to approximately 1,560 hours a year, allowing the bulb to last over a year. The actual lifespan also depends on the teacher's usage habits; with proper maintenance (proper warm-up and cool-down times) and regular dust cleaning, they can often exceed the manufacturer's specified lifespan.
It is advisable to budget twice the price of the projector when purchasing, e.g., for a projector costing 30,000, it's best to calculate 60,000 in the buyer's mind, with the extra 30,000 reserved for future repairs and purchasing two bulbs.
We recommend: This is the projector's Achilles' heel! Although projectors are cheaper than large-screen TVs (e.g., 90 inches), TV prices decrease every year. Before purchasing a projector, confirm whether a large-screen TV could serve as a substitute, as TVs are generally brighter and clearer and do not require bulb replacements.
Short throw or ultra-short throw projectors are commonly used in educational settings. With modern individuals placing increasing emphasis on entertainment and the need for high-quality large images in small spaces, the usage of short throw and ultra-short throw projectors for home entertainment has also gradually increased, becoming the hottest application. Traditional projectors require a certain distance to project large images, making it challenging to meet the demand for large images in space-constrained modern living.
Short throw or ultra-short throw projectors can project large images from short distances, making them essential tools in the teaching market. When using traditional projectors, speakers may experience glare and dizziness from direct light, and shadows can disrupt the image. With short throw projectors, due to their close projection, speakers no longer experience glare or dizziness from direct light, and shadows will not obstruct the projected image.
Ultra-short throw projectors require a flat screen to avoid image distortion or uneven brightness issues.
Moreover, traditional projectors are often installed at lower positions, which can obstruct the camera's ability to capture the supplementary classes. In contrast, short throw and ultra-short throw projectors, because they are installed at higher positions, do not face this issue.
We recommend: Short throw and ultra-short throw projectors tend to be more expensive, and unless speakers stand in front of the projector, short throw projectors may not be necessary for home use. In small living rooms, a larger TV is often more suitable.
Regarding screen materials, pearl white and matte white are the main types.
Basically, the base materials for both types of screens are the same, with the difference being that pearl white screens are covered with tiny glass beads to enhance the reflection of light during projection. Generally speaking, if the light control in the viewing environment is not ideal, and the projector's light output lumens are insufficient, particularly if projecting sizes larger than 100 inches, pearl white material screens may be selected to make the projector's job easier.
Relative to earlier projectors, most had low light output strength, prompting most users to select pearl white screens, thus overlooking the advantages of matte white screens. What are the benefits of matte white screens? Firstly, their overall brightness uniformity is better than that of pearl white screens, meaning that there won't be darker corners with a brighter center, which also means that using a matte white screen reduces the likelihood of color bias (one side leaning blue and the other red).
The second advantage is that it improves the projection of lines; this is akin to drawing a line on sandpaper versus drawing on a flat sheet of paper; naturally, the latter results in straighter lines. Matte white screens share this trait, making colors appear more vivid, and object representations feel more substantial. Therefore, when adjusting the projector, it can be beneficial to reduce brightness and contrast further to achieve better depth and solidity!
Of course, if you choose to use a matte white screen, a prerequisite is strict control over the light sources in the viewing environment. Otherwise, it is still advisable to opt for the higher gain pearl white screen!
We recommend that you choose based on the refractive characteristics of the screen material. If the projector is installed above (projecting down), remember to use a matte white screen, as it is less prone to reflections. If the projector is below (projecting up), you can opt for a pearl white screen.
We recommend: Commercial projectors should use projection screens, while home projectors can do well on white walls!
When installing projectors, images can occasionally appear distorted due to vertical angle issues. Most projectors now have built-in keystone correction features that digitally correct trapezoidal images into rectangular forms. Some high-end projectors even feature automatic keystone correction, adjusting themselves to a rectangular image.
The so-called side projection function allows projectors to be placed at the left or right sides, such as next to a sofa on a side table or in a corner, resulting in a trapezoidal image. By using the projector's internal horizontal keystone correction feature, the projection angle can be adjusted to accommodate various space layouts.
We recommend: This feature is now standard on most projectors, but it’s still good to keep an eye on it.
To avoid significant quality degradation due to keystone correction, some projectors also feature lens shift capabilities, allowing the entire optical lens to be shifted horizontally or vertically, adjusting the projection image position and increasing installation flexibility.
We recommend: Ensure the projector has lens shift functionality.
When reviewing projector hardware specifications, lenses are often overlooked. However, using a glass optical lens ensures that the image retains clarity, dimensionality, sharpness, and overall quality during projection onto the screen.
Additionally, since most projectors currently use high-pressure mercury lamps, which generate extremely high heat, non-glass lenses have lower heat resistance. Under the same temperature and prolonged use, they are prone to deformation, resulting in unclear images.
We recommend: Most high-end or commercial models have glass optical lenses. If you're purchasing a general home projector, be sure to confirm whether the lens is glass or plastic.
Having HDMI digital ports is essential to receive high-definition sources and achieve HD-level image quality.
The High-Definition Multimedia Interface (HDMI) is used to connect output devices to video monitors or digital televisions. HDMI can transmit large amounts of uncompressed audio and video digital data streams at high speed. Since audio and video signals are handled by a single cable, it reduces the number of cables needed to set up a home theater.
Mobile High-Definition Link (MHL) is a product of the era of smart mobile communications. MHL can transmit Full HD images and sound, allowing high-definition audio and video content on smart mobile devices to be streamed to projectors, TVs, and computer monitors for playback, easily transferring from small to large screens, and it can also charge the mobile device, ensuring a continuous joyful experience.
Considering the recent emergence of many smart devices like TV boxes and TV sticks, some projectors even offer 1.5A USB power supply for charging devices, reducing wiring complexities.
If you want to watch 4K HDR high-resolution videos on the projector, the HDMI port must be HDMI 2.0a or higher and support HDCP 2.2.
We recommend: HDMI is a must; do not buy a projector without HDMI! If the budget allows, go straight for HDMI 2.0a or 2.1.
HDR stands for High-Dynamic Range, which means "high dynamic range." When we shoot in scenes with significant brightness and darkness differences, we often find that bright areas become overexposed and "blurred," while dark areas turn completely black, making it hard to see details. By using "HDR mode," this issue can be improved. HDR is one of the most important new video technologies since standard definition transitioned to HD. Every TV with HDR capability is compatible with HDR10, as this is the minimum specification. The HDR10 format allows a maximum brightness of 1,000 nits and a color depth of 10 bits. Compared to conventional SDR (standard dynamic range), HDR10 allows image brightness to exceed twice that of SDR, with corresponding increases in contrast and a color palette of over 1 billion shades, compared to about 16 million in SDR. However, the effectiveness of HDR10 depends on the quality of the TV you view it on. When used correctly, HDR10 makes video content look exceptionally good.
HDR10+ takes all the benefits of HDR10 and enhances them, increasing the maximum brightness to 4,000 nits, thus boosting contrast. However, the significant difference is in how HDR10+ handles information. In HDR10, the "metadata" provided by the content source is static, meaning a single set of values is created for the entire content, like a full movie. HDR10+ makes this metadata dynamic, allowing it to change for each frame of video. This means each frame is processed with its own set of color, brightness, and contrast parameters, making the image look more lifelike.
HDR10+ is not currently the best format on the market. Dolby Vision technology, developed by Dolby Labs, is an advanced HDR format. Dolby Labs is renowned for its Dolby Digital and Dolby Atmos audio technologies. Dolby Vision is very similar to HDR10+, using dynamic rather than static metadata to provide unique HDR processing for each frame. However, Dolby Vision offers higher brightness, up to 10,000 nits, and more colors, including 12-bit depth, with an astonishing 68 billion shades.
One reason Dolby Vision is less widespread than HDR10 is that it is a proprietary technology, and companies wanting to implement it in content or hardware must pay licensing fees. In contrast, HDR10 and HDR10+ are open-source and royalty-free, so their adoption rates may explode in the coming years.
In summary, HDR10+ is a new format for HDR that offers higher levels of brightness and contrast, along with more realistic colors and details.
We recommend: Supporting HDR10 colors is basic; having HDR10+ is a trend, and if it also supports Dolby Vision, it would be even better!
The projector's resolution needs to reach at least 1920x1080 pixels for Full HD quality.
Resolution, referred to as "解析度" in Taiwan, "解像度" in Hong Kong, and "分辨率" in Mainland China, refers to terms like SDTV (720x480), HDTV (1280x720), Full HD (1920x1080). The numbers indicate the number of pixels contained in length and width; higher resolution indicates better image quality and the ability to express more details, although larger files result. The aspect ratio is the width-to-height ratio of the screen, with common ratios being 4:3, 16:9, and 16:10. Traditional televisions, computer displays, and presentation slides often used a 4:3 ratio, while HDTV and Blu-ray movies have shifted to a 16:9 ratio.
4K resolution is gradually becoming mainstream, with two specifications: 3840×2160 and 4096×2160 pixels. 4K is four times the size of Full HD, offering very fine image quality. If your reason for purchasing a projector is to watch Netflix or play PlayStation or Xbox, spending extra money on a 4K projector will undoubtedly be worthwhile.
We recommend: Do not buy anything below 1920x1080 pixels! For movies and gaming, choose a 4K projector; if your budget allows, go straight for a 4K HDR projector.
Conference presentations often require an HDMI cable, limiting presenters to their seating positions within the conference room. With the increasing convenience of smart mobile devices, more and more employees and companies desire the ability to project content directly from their smartphones, tablets, or laptops. Additionally, many binge-watchers prefer using their phones or tablets for viewing content. However, since the screens on smartphones and tablets are small, prolonged viewing can strain the eyes, and many exciting details in videos remain unseen.
Wireless projection can resolve the issues mentioned above, allowing users to instantly project good ideas found on their phones wirelessly.
There are projectors on the market that come with built-in Android operating systems, significantly enhancing convenience, which you may consider.
We recommend: HDMI projection is stable, while wireless projection is convenient. If multiple users will be using the projector or if your environment makes running an HDMI cable impractical, choose a projector with wireless projection capabilities.
In the past, using a projector required connecting to a computer to display videos or presentations. Now, the new generation of projectors comes with built-in Android TV and can connect to the internet directly. In addition to supporting wireless projection from laptops or mobile devices, these projectors can also access YouTube or play PPT presentations, making them extremely useful for busy modern individuals or the new internet generation.
We recommend: If the projector has built-in Android TV, it saves the hassle of connecting to a computer.
Speakers refer to the sound output; in the past, projector speakers were merely acceptable, with low volume and poor quality, leading users to external audio equipment. However, with the rise of home entertainment and individualism in the market, along with advancements in portable sound technology, many home projectors have improved their speaker quality, with some even matching audio equipment levels.
When choosing speakers, pay particular attention to output power, commonly measured in watts (W); the higher the wattage, the louder the sound. If the environment where you intend to use the projector is larger or more spacious, high-wattage speakers are necessary. Another consideration is whether the audio output supports DTS-HD, Dolby Audio, or Dolby Atmos.
DTS-HD includes three levels: DTS-HD Master Audio, DTS-HD High Resolution Audio, and DTS Digital Surround Sound. The first two formats can provide 7.1-channel output, while DTS Digital Surround Sound can support a maximum of 6.1 channels. DTS Digital Surround Sound is the original DTS decoding format, with a data rate twice that of standard DVD audio (about 1.5 Mbps). In a 6.1 channel scenario, the sample frequency can reach 48 kHz/24 bits and can be boosted to 96 kHz/24 bits in a 5.1 channel situation. DTS-HD High Resolution Audio can offer 3 Mbps on HD-DVD and 6 Mbps on Blu-ray discs, with a sample resolution of 96 kHz/24 bits per channel. The performance of DTS-HD Master Audio is even more impressive; it can accommodate 18 Mbps of data flow on HD-DVD and up to 24.5 Mbps on Blu-ray. For two-channel output, the sample frequency can reach 192 kHz/24 bits.
Dolby Audio technology is a powerful suite used to deliver rich, clear, and impactful audio for cinemas, homes, and on the go. By enhancing the auditory experience for content enjoyed through broadcasting, downloading, streaming, cinema playback, or optical discs, this technology further amplifies the emotional impact of entertainment. With Dolby Audio technology, movies, TV shows, music, and games can achieve elevated auditory experiences across multiple levels. Dolby Audio can provide surround sound effects with up to 7.1 channels, including virtual surround sound from any source transmitted via headphones.
In real life, sound comes from all directions, but traditional channel-based surround sound systems can only project sound and audio effects across the horizontal plane, including front, left, right, and rear. Dolby Atmos achieves an incredible immersive experience because it reconstructs every subtle sound in a scene based on its source direction—including vertical space. You will be immersed in an extremely realistic three-dimensional audio space, with precisely positioned ambient sounds surrounding you as in real-life situations. The experience is magical and exhilarating, sometimes even thrilling or hilarious, but always captivating.
Compared to traditional channel-based home theaters, Dolby Atmos systems offer greater flexibility and adaptability. When using an AV receiver with Dolby Atmos functionality to play Dolby Atmos format videos, the receiver maps the Dolby Atmos audio elements to the corresponding speakers, utilizing layered audio tracks for innovative technology, resulting in clearer, more accurately positioned cinema sound that faithfully reflects the creator's original intentions. The Dolby Atmos format includes metadata that automatically generates optimal audio tracks for the cinema.
We recommend: If your usage environment lacks additional sound systems, or if you frequently transport the projector to different locations for screenings, a projector with decent built-in speakers will be your best choice. Whether or not it supports DTS-HD or Dolby depends on whether you plan to watch movies on the projector; Netflix currently supports Dolby Atmos.
When you want to project images directly onto a blackboard, we recommend choosing a projector with a blackboard mode. This type of projector can correct color deviation when projecting onto a blackboard, adjusting the projection color to compensate for the screen color. Even when projecting onto colored walls, wall color correction can still produce accurate colors using built-in four-color correction modes (red/yellow/blue/green) to enhance projection quality.
We recommend: If you are an educational unit using a blackboard, this mode is very useful but not applicable for whiteboards. Home users likely do not need blackboard mode as there shouldn’t be a blackboard in your home!
The interactive projection feature allows you to write any text, lines, and patterns on the screen without using a dedicated interactive whiteboard. Projectors with interactive projection functionality essentially offer basic electronic whiteboard capabilities.
We recommend: Interactive projection is often used for teaching and explanations, making it very useful for educational units! Home use does not require interactive projection, and it is unnecessary for company use.
When purchasing a projector, instead of comparing specifications from various brands on a computer, it is better to see the effects in person. If the manufacturer is willing to allow a test, direct testing is the best way to find the lumens most suitable for your environment and needs.
We recommend: This is based on experience; seeing in person may not always be accurate. Testing in the classroom or at home for peace of mind is the most reassuring.
When teachers use projectors or electronic whiteboards, if the text is too small or the color differences are too stark, and the podium lights are turned off for long periods, using a projector or electronic whiteboard for an eight-hour class is akin to watching an eight-hour movie, which can cause significant eye fatigue. The biggest drawback of projectors is that they may contribute to deteriorating children's vision; thus, teachers must be more considerate and careful in their correct usage.
Here are some points to note when using projectors:
- If the classroom lacks thick curtains, the effect during sunny days will be diminished, especially if windows next to the podium are not shaded, making it hard for students to see clearly.
- Because projectors have strong brightness and the relative classroom brightness is low, such environments are not good for vision, and long-term use is not recommended.
- If students need to read books on their desks or write exercises while using the projector, a dim environment can severely affect their vision. Over time, students may consider this normal and will not protest. Therefore, teachers should switch back to the lights when students need to write.
- Students should engage in outdoor activities after classes involving projector use.
- For lower-grade elementary students, projector use is not recommended.
- For middle-grade elementary students, use projectors for no more than 30 minutes per session.
- For upper-grade elementary students, use projectors in alternating periods and adhere to the 30/10 rule (rest for 10 minutes for every 30 minutes of screen time).
- Font size: During stop screen teaching, lower grades should use at least 36-point font; grades above middle school should use at least 28-point font.
- Lighting: All lights except those above the screen should be off; the desktop illumination should be at least 350 lux.
- It is advisable to periodically adjust seating arrangements.
- The first row of seats should not be too close to the screen, at least 2 meters away.
The failure rate of projectors is higher than that of televisions. Therefore, before purchasing a projector, it is essential to consider the manufacturer's reputation, the length of the warranty provided, and after-sales service. Projectors are expected to last at least three years, so it is advisable to select models with warranties of three years or more.
Most LCD projectors are made by Japanese manufacturers, although some Japanese manufacturers also produce both LCD and DLP projectors, while DLP is primarily produced by American and Taiwanese companies.
Market brands for projectors include: 3M, ACER, ASK, BENQ, CANON, EPSON, HITACHI, HP, IBM, INFOCUS, JECTOR, JMGO, MI, MITSUBISHI, NEC, OPTOMA, PANASONIC, PHILIPS, PLUS, POLAROID, TOSHIBA, SANYO, SHARP, SONY, VIEWSONIC, VIVITEK.
We recommend: There are many projector brands, so it’s advisable to choose a reputable brand for better assurance.
蘊藏許多助人的知識與智慧。