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True Ergonomics from SurgiTel: The Truth about Declination Angle

ErgoPractice News – June 2020
By Jin Chang PhD

Requirements of True Ergonomic Loupes

True ergonomic loupes should satisfy two basic requirements: safe lower back posture and safe neck posture (or safe head tilt). All loupes with proper working distance can help users work with safe lower back posture, but most loupes force users to excessively tilt their heads, becoming the main cause of chronic neck pain among clinicians. Since loupes can help users work with safe lower back postures, all manufacturers may call their loupes “ergonomic loupes,” but only SurgiTel loupes can be called “true ergonomic loupes” because SurgiTel loupes can meet both requirements by using several patented technologies not available to other manufacturers.

Let Us Review the Differences Between “Saying Ergonomic Loupes” and “Being Ergonomic Loupes.”

Most loupes companies were created to provide their users with magnification on a frame. They focused on creating the best vision they could. This is valuable because if you cannot see your subject well, you cannot do your best work. However, these same companies have recently started adding the word “ergonomic” to their ads. Even though their products have not changed much, or not at all, this word started showing up more often about 4-5 years ago. This is because customers began to realize that living with working pain daily and cutting their career short because of neck injury did not meet their requirements. So, these companies are now saying “us too!”

SurgiTel, however, was created in the early 90s with the specific focus of providing clinicians with the best vision and true ergonomics. During the past three decades, SurgiTel has invented design and manufacturing technologies and thus can offer truly ergonomics loupes with both Through-The-Lens (TTL) loupes and Front-Lens-Mounted (FLM) loupes. Today true ergonomic loupes still are not available from other companies. Figure 1 shows neck postures with various brands of loupes. Only SurgiTel allows for safe tilt under 20-degrees. All these loupes are sold as “ergonomic,” but all but SurgiTel’s force the user to excessively tilt their head.

It is noted that with patented technologies SurgiTel can make loupes with any declination angle so that customers can work with any desired head tilt angle. Clinicians who have worked with large head tilts may feel difficult to work with radically different, small head tilt because changing their work habits will take time.

SurgiTel’s brand motto since the beginning has been “Vision and Ergonomics at Work.” Both are required for good work, and SurgiTel has always designed its products for both. Vision without Ergonomics is a self-defeating situation. SurgiTel started by building only FLM loupes because ergonomic TTL technology was not invented yet. SurgiTel then invented the necessary loupe-ergonomics technologies and only then expanded to sell TTL loupes. It should be noted that SurgiTel is the only company founded with the mission of True Ergonomics as well as excellent vision.

How Can Clinicians Identify Lies About Ergonomic Loupes?

The truth about the declination angle is that manufacturers can easily lie about it. Most clinicians do not know how to measure the declination angle. Many companies use the angle between the axis of loupes and temple arms. However, the true declination angle is between the axis of loupes and the line connecting the top of the ear and the corner user’s eyes. Therefore, without the user, the true declination angle cannot be determined. Figure 2 shows how some companies use a temple arm reference line to overinflate their achieved declination angle.

To learn more about how companies purposefully misrepresent their products using this tactic, view our July 2017 issue of ErgoPractice News.

Why is SurgiTel the Only Company with True Ergonomics?

First, SurgiTel uses patented “Suspended Manufacturing Technology” which allows SurgiTel to create any declination angles customers want to maintain a safe head tilt. The lower loupes optics (called oculars) can be placed compared to the horizontal plane of your eyes, the greater the “looking down” angle can be achieved. Many times, this can be achieved by using lenses that are made as tall as possible to fit the user’s facial features.

The other option is “Suspended Magnification Technology” which secures magnification oculars at the very bottom of a sweep or open lens type (see Figure 3). SurgiTel has patented this technology. As a result of this patent status, many less scrupulous companies will lie to their customers stating this technology is not good for some reason or another. This is done verbally, but not in writing in fear of getting caught in their lie.

View our August 2019 issue of ErgoPractice News where we describe this feature in greater detail.

Second, SurgiTel uses patented “Frames with Unique Pantoscopic Tilt” which allow SurgiTel to create a larger declination angle for TTL loupes and a wide field of view for FLM loupes. One of SurgiTel’s first innovations was creating and using frames with a unique pantoscopic tilt. This is the angle of the lenses as shown in Figure 4.

SurgiTel has created all its titanium frames to have this unique pantoscopic tilt. They have also chosen to work with Oakley because of the pantoscopic tilt they have used on their sports frames for improved eye protection. This gives a “head-start” to great ergonomics.

Third, SurgiTel uses “Proprietary Manufacturing Techniques” which allow SurgiTel to assemble true custom loupes for each customer. With these proprietary technologies, SurgiTel can offer the longest depth of field and true ergonomics. We measure all facial features to customize lens size, nose pads, and custom fitting.

Fourth, SurgiTel uses patented nose pad systems which can make truly custom-fit for all nose types and allow the precision alignment of loupes to eyes. Most loupes by other companies are built off average measurements, not true custom, and thus can be used without much fine-tuning by the clinician.

SurgiTel loupes are truly custom-fitted and allow precision alignment to the user. These precision adjustments are possible with SurgiTel’s patented custom nose pad system, Ergo Fit Nose Pads. They can provide up to 4 mm of vertical adjustability (Figure 5).

View our August 2018 issue of ErgoPractice News where we describe this feature in greater detail.

Why is Achieved Head/Neck Tilt Angle Wearing Loupes the True Test?

Using two side view photos, you can estimate your head tilt angle as shown in Figure 6. The safe head tilt angle is less than 20-degrees.

View our October 2019 issue of ErgoPractice News where we describe how to measure head tilt in greater detail.

Beware of imitators! If they only recently added “ergonomics” to their websites and ads, what were their products before? And even if they did start focusing on ergonomics 4-5 years ago, they are still 25 years behind SurgiTel. Head/neck tilt is the true test. If you or someone you know is working at a greater than 20-degree head tilt, SurgiTel is in order.

Your local SurgiTel representative can provide free consultations. You can look up your local representative at


  • The truth about declination angle is that anyone can lie about it
  • Achieved neck tilt wearing the loupes is the true test
  • SurgiTel is the only loupe company founded with the mission of Vision and Ergonomics
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