How to prevent the keyboard from opening automatically in my Ionic2 App? - ionic2

Question

I am developing a Mobile App using the Ionic2-Framework along with Angular2.
In a section of my app, I have several <ion-slides> with <ion-item><ion-input ...></ion-input></ion-item> on the slides.
When changing the slide, the keyboard opens up without actively touching one of the input-fields. So far, I could only test it on iOS, but I found out that it only happens for type="tel"-inputs
Is there a way to prevent the app from doing this, as I would like the users to choose the time to input by themselves.
The code of my page looks like that:
(I excluded some parts for readability)
<ion-header>
<ion-navbar>
<button ion-button icon-only menuToggle [hidden]="showBackButton">
<ion-icon color="primary" name="menu"></ion-icon>
</button>
<button color="light" ion-button icon-only [hidden]="!showBackButton" (click)="goToPreviousSlide()">
<ion-icon color="primary" name="arrow-back"></ion-icon>
</button>
<ion-title>Title</ion-title>
</ion-navbar>
</ion-header>
<ion-content padding>
<ion-slides (ionSlideDidChange)="updateShowBackButton()">
<!-- Some more slides... -->
<ion-slide style="background-color: white" padding>
<h2 class="slide-title">Hello {{person.name}}!</h2>
<p>Now I need this and that information:/p>
<ion-item>
<ion-label>Day</ion-label>
<ion-input type="tel" fixed [(ngModel)]="person.day"></ion-input>
</ion-item>
<ion-item>
<ion-label>Month</ion-label>
<ion-input type="tel" fixed [(ngModel)]="person.month"></ion-input>
</ion-item>
<ion-item>
<ion-label>Year</ion-label>
<ion-input type="tel" fixed [(ngModel)]="person.year"></ion-input>
</ion-item>
<ion-item-divider></ion-item-divider>
<ion-item>
<ion-label>Height (cm)</ion-label>
<ion-input type="tel" fixed [(ngModel)]="person.height"></ion-input>
</ion-item>
<ion-item>
<ion-label>Weight: (kg)</ion-label>
<ion-input type="tel" fixed [(ngModel)]="person.weight"></ion-input>
</ion-item>
<button ion-button block (click)="goToNextSlide()">Next</button>
</ion-slide>
<!-- Some more slides... -->
</ion-slides>
</ion-content>
If you need futher information, please let me know! I am appreciating any hints! :)