Why Do Teleprompters Use Mirrors?


A teleprompter, otherwise known as an autocue, is a device that displays words or text for the presenter to read. This way, the speaker doesn’t have to memorize loads of paragraphs and, therefore, can concentrate on engaging or connecting with the audience. 

A teleprompter setup often involves a monitor and a reflective screen or glass in front of the camera lens. The monitor shows a mirrored image of the text the reader will be reading, which then reflects onto the glass screen in front of the camera lens. The reflective glass is actually a one-way mirror and is technically called “beamsplitter glass.”

Why Teleprompters Use Mirrors

Aside from the camera and the monitor, the mirror is also a central component of a teleprompter setup. Why do teleprompters use mirrors? Because that’s where the magic happens! The one-way mirror shows the image of the text that will be read. The mirror has a clear coating that allows it to both reflect and transmit light. 

There are several types of teleprompter mirrors or beamsplitter glasses. The most commonly used are 30R/70T or 40R/60T. This means the mirror is either 30% or 40% reflective and 70% or 60% transparent. 

The display will be placed beneath the mirror. The display can be a tablet, laptop, or phone, depending on your available device. However, bigger should be better, allowing you to clearly see the text even from a considerable distance. You should ideally have your script in white letters on a black background for easier reading.

The teleprompter mirror is often put at a 45-degree angle with the display monitor underneath. This way, the text will be displayed and reflected on the glass for you to read. At first, you’ll see the text displaying backward as it’s supposed to when things are reflected on a mirror, but teleprompter apps on your device should have a Flip Text feature. Tap this so that the text is reflected on the mirror as it should.

More About BeamSplitter Glasses

Now, let’s talk more about the reflectiveness and transparency of the beamsplitter glasses. When the text is displayed on the screen, it is reflected into the glass. If the beamsplitter glass is 30R/70T, 30% of the light is reflected and bounced back to your eyes. This is why you can see and read the script.

The suggested white text and black background setup are optimal in reflecting the text to the glass. The white color allows the maximum bounce-off, so to speak, and the black background contrast helps to make the letters stand out.

You may have also wondered where the rest of the light goes if only 30% is reflected off the glass. Well, no need to think any further. 70% of the light goes right through the glass, hence, the “transparency” factor. 

The camera will not pick up the mirrored script in this setup. Because the display is oriented upward, the residual image will continue upward rather than entering the camera directly. On the other hand, the speaker won’t see the camera behind the mirror because he mainly sees the scrolling text. 

How to Choose the Right Beamsplitter Glass

Depending on your needs and where you record your video, you need to choose the right glass for you. 

  1. Normal Beamsplitter Glass

The garden variety beamsplitter glass described in the previous section is the most common type of teleprompter glass. It works best in indoor settings. Perhaps the most significant decision you should make is choosing a 60/40 or 70/30 glass. Some people with vision issues prefer more light being reflected, so if you’re one of them, go for the 60/40 glass. However, with the camera power and additional lighting, having a 70/30 reflective glass won’t cause that many problems, even if you have poor vision.

  • Outdoor Beamsplitter

As its name suggests, an outdoor beamsplitter is designed if you’re shooting a video or giving a speech out in the sun. The bonus tinted coating is the biggest difference between a normal indoor beamsplitter and the outdoor variety. This reduces the glare so you can still clearly see the scrolling text, even in an outdoor setting. 

  • Outdoor Acrylic Beamsplitter

The outdoor acrylic beamsplitter is pretty much like a regular outdoor beamsplitter, except it’s made out of acrylic instead of glass. The main advantage of acrylic beamsplitters is that it’s lightweight and more durable. Variables and accidents can happen outdoors, and it’s not uncommon for glass beamsplitters to get knocked over and break into smithereens. That’s a disaster, especially if that transpires on live TV. The simple but brilliant solution is an acrylic beamsplitter to prevent such scenarios from happening.

  • First Surface Mirror

Made out of glass or acrylic, a First Surface Mirror is the go-to if the speaker needs maximum readability. It is a totally opaque mirror, which means it does not allow light to pass through. In other words, it’s essentially a 100/0 beamsplitter glass. The most significant disadvantage of these mirrors is that you won’t be able to record through them. Therefore, the camera must be positioned at another angle to capture you.

How to Choose the Right Teleprompter For You

While teleprompters have been used in television and professional video production since its inception, choosing the appropriate one can be challenging. There is the question of how far the prompter should be situated from the performer to be read accurately. Besides that, consider how quickly the text needs to scroll, which is usually determined by the person reading it. 

As far as the viewing distance, the primary consideration is the size of the teleprompter. If the speaker presents from up to 19 feet, a 17-inch monitor will do it. If the presenter is only within 13 feet, a 10-inch monitor is generally enough. It is also critical to ensure that the mounting arrangement of the prompter is compatible with the camera, lens, and tripod being used.

How do you figure out compatibility? One marker is weight capacity. The tripod head should have enough weight capacity to support the mass of the teleprompter. First-time customers frequently discover that their tripods cannot sustain the weight of the teleprompter. Therefore, choose a tripod with sufficient payload capacity.

Another factor is if the camera and lens can be placed at the back of the teleprompter hood so that the speaker’s eye line is directly into the camera. Some mirrors are opaque, which allows as little light as possible so that you cannot directly set up a camera behind the teleprompter hood. If you’re making informative videos, this factor is of utmost importance.

Lastly, the last thing that you need to consider is the teleprompter app. An easy-to-use teleprompter app is a game-changer that takes your videos and presentation to another level. Choose software that’s intuitive and should not take too much time to learn. You may check out the Teleprompter app by MK App Solutions for iOS devices and Simple Teleprompter for Android users.  

When to Use Teleprompters

Almost every video production setup may need a teleprompter. Teleprompters are used by newscasters, award show presenters, and even Presidents. Most YouTube channel owners and vloggers have begun to use teleprompters.

If you’re thinking of doing any type of video– whether for social media or a school project– do not get over your head and think you can handle and memorize everything. Nerves could set in any moment, stress rises, and you can have a mini-amnesia and forget what you should say. Of course, a teleprompter is not a cure-all or a pill for your rising heart rate, but you can at least take solace in the fact that what you’re going to say is right there in front of you.

A teleprompter is, without a doubt, one of the most valuable pieces of equipment to have on a production set. It can practically save a project at times. Always include a teleprompter in your production equipment when you need to present a specific script on camera. Otherwise, you’d waste hours trying to perfect something that has an easy solution.

Final Thoughts

If you are new to video production or just trying to polish your videos some more, a teleprompter might be the answer. A teleprompter setup includes a camera, monitor, and mirror. The mirror, or a beamsplitter glass, is imperative because it shows the image of the text that will be read by the presenter. This allows the speaker to look straight into the camera and deliver the lines with optimal eye contact with the audience.

One of the decisions you have to make if you’re thinking of buying a teleprompter is the type of mirror you want to use. You may opt for a 30R/70T or a 40R/60T beamsplitter glass or even an opaque one such as a First Surface Mirror if you’re shooting outdoors. You may choose an optimal reflective mirror for indoor shoots, allowing light to be reflected and bounced back to your eyes so you can read the words clearly. 

Regardless of your choice, see to it that every component is compatible and you have an easy-to-use and intuitive teleprompter app.


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